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B18_copertina_R_OK C August 20-28,2004 -

Field Trip Guide Book - B18 Associate Leaders:M.Boni,L.Meinert Leader: M.Benvenuti Pre-Congress () AND ELBAISLAND SOUTHERNTUSCANY SKARN DEPOSITSIN 32 Volume n°2-fromB16toB33 GEOLOGICAL CONGRESS nd INTERNATIONAL B18 28-05-2004, 17:20:11 The scientific content of this guide is under the total responsibility of the Authors

Published by: APAT – Italian Agency for the Environmental Protection and Technical Services - Via Vitaliano Brancati, 48 - 00144 Roma - Italy

Series Editors: Luca Guerrieri, Irene Rischia and Leonello Serva (APAT, Roma)

English Desk-copy Editors: Paul Mazza (Università di Firenze), Jessica Ann Thonn (Università di Firenze), Nathalie Marléne Adams (Università di Firenze), Miriam Friedman (Università di Firenze), Kate Eadie (Freelance indipendent professional)

Field Trip Committee: Leonello Serva (APAT, Roma), Alessandro Michetti (Università dell’Insubria, Como), Giulio Pavia (Università di Torino), Raffaele Pignone (Servizio Geologico Regione Emilia-Romagna, Bologna) and Riccardo Polino (CNR, Torino)

Acknowledgments: The 32nd IGC Organizing Committee is grateful to Roberto Pompili and Elisa Brustia (APAT, Roma) for their collaboration in editing.

Graphic project: Full snc - Firenze

Layout and press: Lito Terrazzi srl - Firenze

B18_copertina_R_OK D 24-05-2004, 10:01:22 Volume n° 2 - from B16 to B33

32nd INTERNATIONAL GEOLOGICAL CONGRESS

SKARN DEPOSITS IN SOUTHERN AND ISLAND (CENTRAL ITALY)

AUTHORS: M. Benvenuti (Università di Firenze - Italy) M. Boni (Università “Federico II” di Napoli - Italy), L. Meinert (Washington State University - USA)

Florence - Italy August 20-28, 2004

Pre-Congress B18

B18_R_OK A 24-05-2004, 10:03:10 Front Cover: Historic site of Rocca San Silvestro in the mining district

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Leader: M. Benvenuti Associate Leader: M. Boni, L. Meinert

Introduction historical, mineralogical, and economic importance. The field trip will start with a general overview at Aim and Localities of the Field Trip the historic site of the Etruscan town of . IGC field trip B18 will investigate the classic skarn Following this, we will travel by ferry to the Island localities of Tuscany and the Island of Elba. Tuscany of Elba to examine the Fe-skarns at several localities. includes several different skarn types but the most The second day we will focus on the classically famous, and the ones that we will visit on this field zoned Zn-skarn system around Campiglia. The trip trip, are the Fe and Zn skarns at Isola d’Elba and will conclude with a visit to the archeometallurgically in the Campiglia Marittima district. These are of interesting beach slags at the Baratti Gulf. Volume n° 2 - from B16 to B33 n° 2 - from Volume

Figure 1 - Itinerary of the field trip.

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Volume n° 2 - from B16 to B33 B18 - B18 Leader: M.Benvenuti district: trip (i.e.,ElbaIslandandtheCampigliaMarittima The two areaswhichwillbevisitedduringourfield Geology andgeodynamics Regional setting Apennines (modifiedfromBoninietal.,2001). Figure 2-Geologicalsketch-map ofthenorthern become progressively youngereastward. stratigraphic unitsdepositedintheforedeepsystem, tion ofthethrustfront,–Miocenetectono- gravity sliding.Duetotime–spaceoutward migra- very importantdetachment planeforthrustingand Sea area. The baseofthethickevaporitic layerisa (Burano Fm.),gradingtodolomitesinthe Adriatic on about1000–1500m-thick evaporites composed ofcarbonaterocks.Bothsuccessionsrest lower successionofMesozoic–Cenozoicage,mainly formed bysiliciclasticforedeepsediments,anda 3000 m-thicksuccessionofOligocene–Mioceneage, and –Marcheunitsconsistofanupper2000– the Adria Platesincethemiddle Triassic. The Tuscan units, originallydepositedonthepassive margin of tectonically overlie the Tuscan andUmbria– lites withtheirJurassictoEocenesedimentarycover, yan ocean). The Ligurianunits,consistingofophio- the Ligurian–Piedmontesesectorof Alpine Teth- rides), originallydepositedinanoceanicrealm(i.e. 3 (Finetti etal.,2001). As schematicallyshown in units, accompaniedbysecond-orderback-thrusts mainly composedofapileNE-verging tectonic chain ( , theuppermostareLigurianUnits(orLigu- Fig. 2 Fig. 1 ). The Northern Apennines chainis ) belongtotheNorthern Apennines Fig. range ofmafic tointermediaterockssuchaslam- acid peraluminousrhyolitesandgranites,awide Peccerillo etal.,1987). east (Civetta etal.,1978;Ferraraand Tonarini, 1985; Ma, showing atrendofdecreasingagesfromwestto sive bodieswereemplacedinthetimespanof8to0.2 land (mainlyinsouthern Tuscany). Volcanic tointru- ent crustallevels intheNorthern Apennines hinter- variety ofmagmaticbodieswereemplacedatdiffer- orogeny (fromLateMiocenetoPleistocene),alarge During thepost-collisionalphaseof Apenninic -Quaternary Magmatism Figure 4-Locationandageofmagmaticrocks ofthe Tuscany MagmaticProvince (Peccerillo etal.,2001) Figure 3-Schematic stratigraphiccolumnsofthe Tuscan andUmbria-Marche units

They includecrustalanatectic (from Finetti etal.,2001) 24-05-2004, 10:03:30 SKARN DEPOSITS IN SOUTHERN TUSCANY AND ELBA ISLAND CENTRAL ITALY B18

proites, high-potassium calcalkaline and shoshonitic rocks (Fig. 4). Rock compositions straddle the I and S fields of Chappel and White (1974), the most basic rocks being mainly I-type and the high-silica ones S- type (Peccerillo et al., 2001, and references therein). Most of the acid rocks appear to have undergone mixing and mingling with various types of mantle- derived calcalkaline to potassic melts (Poli, 1992). Mafic rocks, in fact, are commonly found as micro- granular enclaves and veins in most acid extrusive and intrusive bodies of the Tuscan Province. Several geochemical and petrological features, further sug- gest a heterogeneous mantle source for the mafic melts (Peccerillo, 1999). According to Peccerillo et al. (2001) the overall petrogenetic history for the Tuscan Province can be described in three main steps: 1) subduction-related metasomatism of upper mantle (both asthenospheric and lithospheric) by interac- tion with upper crustal material; 2) variable degrees of partial melting of heterogeneous mantle due to Figure 5 - The main mining districts of Tuscany asthenospheric uprise, and formation of various types (modified after Tanelli, 1983) of magmas; 3) injection of mafic magmas into the continental crust, uprise of isotherms, onset of crustal district) and -(-) skarns (Temperino anatexis, and acid-mafic magma mingling. mine in the Campiglia M.ma district; Serrabottini near ). These deposits have been Ore Geology studied by Bartholomé, Evrard, 1970; Corsini et For about 30 centuries, Tuscany has been one of the al., 1980; Dimanche, 1971; Tanelli, 1977; Lattanzi, most important mining producing Tanelli, 1985; Del Tredici (1990), Torrini (1990) and a large variety of resources, including , , Dünkel (2002). According to Tanelli (1977) the Tus- base metals, geothermal steam and several industrial can skarn deposits formed by replacement of Triassic minerals and rocks (Lattanzi et al. 1994, and refer- ences therein). Today the mining industry in Tuscany is limited to industrial minerals (, halite), ornamental stones, and building materials. The Tus- can metallogenic province includes (Figs. 5 and 6): the Fe oxides deposits of Elba Island, the pyrite (± barite ± Fe oxides) deposits of southern Tuscany and Apuane , the base-and precious-metals deposits of the “” district (southern Tusca- ny), the Hg deposits of the Monte Amiata area, the Sb deposits of the Capalbio-Monti Romani belt (cf. Cip- riani, Tanelli, 1983; Tanelli, 1983). The newest addi- tion to the metallogenic framework of Tuscany, is the discovery in the mid ‘80s of “Carlin-type” epithermal B16 to B33 n° 2 - from Volume mineralization. Most of the Au prospects, of lim- ited economic importance, are closely related to Sb deposits (Tanelli et al., 1991; Lattanzi, 1999). A number of different skarn deposits occur in the southwestern portion of the Tuscan metallogenic province (Fig. 7): they include calcic iron skarns (Capo Calamita, Ginevro, Sassi Neri and Ortano at Figure 6 - Distribution of main ore types Elba Island; in the Colline Metallifere of southern Tuscany

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Volume n° 2 - from B16 to B33 B18 - B18 Leader: M.Benvenuti magmatic rocks(Lattanzietal.,1991). of lead(andothermetals?)fromNeogene-Quaternary tima andNiccioletadepositsmayreflectcontribution tion ofpyrite andgalenafromtheCampigliaMarit- On theotherhand,uniformleadisotopecomposi- sulfides/sulfates from Permo-Triassic countryrocks). compatible withalocal,nonmagmaticsource(i.e., tion ofsulfurfromthe Temperino skarndepositis Corsini etal.(1980)maintainthatisotopiccomposi- for Tuscan skarndepositsarestillpoorlyconstrained. with attendantswarms ofapliticandpegmatitic dikes, presence ofanextensive Mio-Pliocenemagmatism, Tyrrhenian basin.Otherelementsofinterest arethe tion ofthe Apenninic chainaftertheopeningof the reconstructionoftectono-stratigraphicevolu- Northern Apennines, ElbaIslandisakey elementfor Due toitslocationmidway betweenCorsicaandthe The geologicframework Elba Island mation ( for instanceapliticdikes appeartopredateskarnfor- does notnecessarilyimplyageneticlink:atGinevro, of magmaticrocksincloseproximitytoskarnbodies various distances(Niccioleta,Ortano). The presence with magmaticrocks(e.g.,at Temperino mine),orat Tuscan Province. Skarnbodiesmaybeincontact crustal levels oftheNeogenemagmaticrocks processes triggeredbytheemplacementatshallow carbonate rocksofthe Tuscan Unitbymetasomatic (after Tanelli, 1977) Figure 7-LocationofTuscan skarndeposits cf. Dimanche,1971).Source(s)ofelements the stockcauseddeactivation ofthe et al.,2003). At 6.2-5.0Ma,theemplacementof exploited atLaCrocetta andMarcianamines(Maineri (sericite replacingprimaryalbiteandK-feldspars) porphyritic aplitesandformationofthe“eurites” and resultingpervasive hydrothermalalterationof The ElbaCentralFault caused intensefluidcirculation top ofMonteCapannepluton. laccolith complex) from theiroriginalpositiononthe upper platerocks(includingComplex V withintruded controlled theeastward translationofabout10km detachment fault (ElbaCentralFault), which triggered themovement ofanimportant extensional that theemplacementofMonteCapannepluton rocks (>8.5-6.85Ma).Dinietal.(2002)suggest laccolith complex madeofsubvolcanic porphyritic associated withtheMonteCapannepluton),anda pegmatitic dikes (thelatteralmostexclusively found Azzurro (6.2-5.0Ma),several swarms ofapliticand pluton (6.9Ma),themonzograniticstockofPorto al., 2003,andreferencestherein):theMonteCapanne shallow crustallevels (cf. Dinietal.2002;Maineri the emplacementofseveral magmaticintrusionsat sional phase. This stage was alsoaccompaniedby orogeny, andlateraffected byanimportantexten- tion duringthecompressionalstageof Apenninic were deformedandpiledupintotheirpresentposi- ited inquitedifferent palaeogeographicdomains, thrust surfaces. The various units,originallydepos- are separatedeachotherbyroughlyNSverging over- characterised byageneraltoptoeastvergence, and IneasternElbatheunitsofthistectonicpileare otti etal.,2001andreferencestherein). Unitand(9)(Bortol- Ophiolitic Unitwithseven subunits; (8) (5) Tuscan NappeUnitand(6)GràsseraUnit;(7) Acquadolce Unit;(4)-RoccastradaUnit, (1) Porto Azzurro Unit;(2)OrtanoUnitand(3) (from thegeometricallylowermost upwards): is madeupbythefollowing ninemajortectonicunits The tectonicframeofcentralandeasternElbaIsland sional events tookplace(Bortolottietal.,2001). /? Quaternarysyn-andpost-magmaticexten- (Tuscany Domain)margins, intheLateMiocene- deformation oftheEuropean(Corsica)and Adriatic Eocene-Lower Miocenecollisionandpolyphase ocean (Ligurian-PiedmonteseBasin). After theUpper tiary withtheconsumptionofwestern Tethyan evolution begins intheLateCretaceous-Early Ter- tory startsinthePalaeozoic, but its Alpine tectonic ore deposits.ElbaIsland’s long-living geologichis- as welltheoccurrenceofworld-famous iron 24-05-2004, 10:03:45 SKARN DEPOSITS IN SOUTHERN TUSCANY AND ELBA ISLAND CENTRAL ITALY B18

Elba Central Fault, although additional eastwards (data from Fabri, 1887; Pullè, 1921). To preserve this tectonic translations took place along another major long mining tradition a “Mining and Mineralogical low-angle fault, the Zuccale fault (Pertusati et al., Park” has been recently established in eastern Elba 1993). The emplacement of the Porto Azzurro pluton (cf. Tanelli and Benvenuti, 1999). caused also a strong thermometamorphic imprint As shown in Figure 8, the Fe deposits of Elba Island on the geometrically lowermost Units of the Elba are restricted to a relatively narrow belt extending NS structural edifice (namely, the Porto Azzurro, Ortano along the eastern coast of Elba Island, from Monte and Acquadolce Units). Crosscutting relationships Calendozio (Rio Albano mine) to the Calamita between the Zuccale fault and aplitic dikes indicate promontory. The ore bodies range from stratiform to that the detachment postdated, at least partially, the pod-like or vein-type, although the first appears to be emplacement of the magmatic dikes. The last tectonic dominant (Zuffardi, 1990). Stratiform Fe bodies are stage at Elba Island is mainly represented by N-S predominantly hosted by Palaeozoic-Triassic forma- trending high-angle extensional faults, affecting the tions belonging to the Tuscan domain. Many Fe ores entire N-Tyrrhenian basin. This last episode ended are associated with faults (Debenedetti, 1952; Gil- before about 3.5 Ma (Keller and Pialli, 1990). lieron, 1959): a first set of thrust faults, striking NS and dipping 30°-45° W, corresponding to the thrust Geology, mineralogy and textures surfaces among the various tectonic units, and two of Elba iron deposits sets of normal, high-angle faults, one striking NS and Iron ores from Elba Island have been mined without dipping 30°-60° E, the other one with strike NE-SW interruption for almost three millennia, since the and dips of 45°-70° to NW or SE. early Etruscan mine workings (early 1st Millennium As reviewed by Tanelli and Lattanzi (1986) there is BC: Corretti and Benvenuti, 2001) up to about twenty disagreement in the literature about whether all of years ago (1981, closure of the Ginevro mine). At the Fe deposits are genetically associated with late- least 60 million tons of Fe ore have been extracted Apenninic granitic stocks or whether in some cases from Elba deposits from ancient times to the present the intrusions simply metamorphosed and partly Volume n° 2 - from B16 to B33 n° 2 - from Volume

Figure 8 - Location of main iron deposits of Elba Island. Legend: 1) Rio Albano; 2) Rio Marina; 3) Ortano; 4) Terranera; 5) Calamita; 6) Ginevro; 7) Sassi Neri.

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Volume n° 2 - from B16 to B33 B18 - B18 Leader: M.Benvenuti goethite andtraceamountsofbasemetalsulfides. lenses andmassive bodiesofmagnetite±, associated withbothtypesofskarn,andconsisted otti etal.,2001). The exploited oreswerespatially dolostones anddolomiticlimestones”ofBortol- and theoverlying carbonaticformation(“crystalline at thecontactbetweenMt.CalamitaFormation hedenbergite skarn(Torrini, 1990)developed mostly form garnet(andradite)-richskarnandlesserilvaite- by thePorto Azzurro Unit. At CapoCalamitastrati- Ginevro several skarn-bearingirondeposits(CapoCalamita, dent intheCalamitaPeninsula(see Azzurro pluton. This associationisparticularlyevi- associated withapliticdikes linked tothePorto Fe oresandskarnsofsoutheasternElbaIslandare age ofonehematitesample(Lippoltetal.,1995). development, basedupona7.3 tion appearstobecoeval andcogeneticwithskarn the nearbyPuntadelleCannelle. The ironmineraliza- are incloseproximitytoskarnbodiescroppingoutat ranera withintheMonticiano–RoccastradaUnit,and Lenses ofhematite+pyrite ±magnetiteoccurat Ter- Acquadolce Unitfromtheoverlying Ortano Unit. phyllites alongacataclastichorizonseparatingthe skarn bodies,whichreplacemarblesandcalcareous magnetite), associatedwithpyroxene-epidote-ilvaite ferent oremineralogy(pyrite, pyrrhotite ±hematite, and Capod’Arco. The Ortanodepositshows adif- skarn bodiesoccuratOrtano,Porticciolo, Tignitoio Lotti (1886,pp.205-206).Moving southwards, other the Acquadolce calc-schists,asreportedindetailby 9 extend alongthecoast(Torre diRioskarns, ± ,chlorite,magnetite,pyrite andpyrrhotite large skarnbodieswithhedenbergite-ilvaite-epidote 2001). ImmediatelysouthofRioMarinatown, very of theMonticiano-RoccastradaUnit(Bortolottietal., overlying JurassictoOligocenecarbonaticformation which arenow interpretedastectonicslicesofthe masses (the Vigneria limestonesofGillieron,1959), skarn bodiesreplacingwedge-shapedcarbonatic in the1950srevealed theexistence ofhematite-pyrite at depth.Drillingandlimitedunderground workings Even atRioMarinaskarnbodieswereencountered and/or apliticdikes becomesmoreanddistinct. sula, theassociationofironoreswithskarnbodies Moving fromRioMarinatowards theCalamitaPenin- Palaeozoic age(stage thermal sedimentaryenvironments of Triassic and/or least pre-concentrated,insedimentaryand/orhydro- remobilised theironoresthatwereformed,orat ). Skarnmineralsoccuralongschistosityplanesof (Fig. 9a) , SassiNeri,Stagnone)arehosted ii ofLattanzietal.,1994). ± 0.4Maradiometric Fig. 8 ), where Fig. Colline Metallifereand Alpi Apuane) isnotwell of ElbaIslandandother Tuscan districts(namely, As mentionedpreviously, thegenesisofirondeposits 1990). the garnetskarnandmagnetitelenses.(Torrini, exploited atCapo Calamitaatthecontactbetween ± malachite,azurite,chalcantite,etc.)werelocally of Fe-Cusulfides (pyrrhotite, pyrite, chalcopyrite normally forminalateparageneticstage.Masses abundant inthemagnetite-typedeposits,wherethey Marina –Rio Albano deposits,aresignificantly more Sulfides, whicharevery rareorabsentintheRio observed by Torrini (1990). early cassiterite+pyrite assemblage,whichwas not and Torrini (1990). The formerauthordescribesan posed fortheCalamitairondepositbyDünkel (2002) Figure 10 al., 1976). Bianco andCapoCalamitamines(cfr. Calanchiet exploited inthepast,especiallyatRio Albano, Capo tionary, sometimesstalactitic), whichwereactively types andmorphologies(earthy, massive, concre- mary Femineralsarelimoniticaggregates ofvariable primary pyrite. The final alterationproductsofpri- being derived fromoxidationandremobilisationof ±pyrite (±quartz)assemblageisparageneticallylate, Deschamps etal.(1983)suggestedthatthehematite ± pyrite, mostcomingfromtheRioMarinastopes. crystals ofhematite(variety “oligisto”=glazeiron) Elba isespeciallyfamous worldwide foritsbeautiful (1990) hasobserved thesametexture atSassi Neri. (1977), Torrini (190)andDünkel (2002).Del Tredici confirmed byCocco andGaravelli (1954), Tanelli vite), asfirst suggested by Vom Rath(1870)and as pseudomorphsafterprimaryhematite(mushketo- of theCalamitapeninsula. Typically, magnetiteoccurs sulfides) isenriched intheskarn-associateddeposits deposits, whereasmagnetite(±pyrite±Cu,Pb,Zn,As,Bi a generalrule,hematiteisdominantinthenorthern relatively simple,beingmadeupofFeoxides. As Primary oremineralogyofElba’s irondepositsis detailed informationisthusavailable. a drillingproject,but was never exploited; no Finally, theStagnonedepositwas recognizedthrough minor amountsofhedenbergite, ilvaite andepidote. associated withgrossular-almandine garnetandonly Del Tredici, 1990). The skarnscontainferropargasite, a greatabundance ofaplitic dikes (Dimanche,1971; tion totallyreplacedthecarbonaterocksandthereis deposits. At Ginevro, forinstance,skarnmineraliza- higher temperatureandmorereducedthantheother The Ginevro andSassiNeridepositsappeartobe shows thetwo parageneticsequencespro- 24-05-2004, 10:03:53 SKARN DEPOSITS IN SOUTHERN TUSCANY AND ELBA ISLAND CENTRAL ITALY B18

Fig. 9 - Photographs of Elba Fe skarn features: a) Open Fe Ginevro mine along the Elba coast b) Interlayered brown garnet and green pyroxene at Rio Marina c) Coarse-grained radiating crystals of hedenbergitic pyroxene cut by black ilvaite veins at Capo Calamita d) Euhedral black ilvaite crystals intergrown with hedenbergitic pyroxene at Rio Marina e) Isoclinally folded metasedimentary host rocks at Rio Marina f) Distal pyroxene- magnetite veins cutting marble at Capo Calamita g) Beach slag deposit from early mining activities along the Baratti Gulf. Volume n° 2 - from B16 to B33 n° 2 - from Volume

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Volume n° 2 - from B16 to B33 B18 - B18 Dünkel (2002);(B):Torrini (1990).Thevertical dashedlinesindicatedeformation episodes. Figure 10-Paragenetic sequencesoftheCapoCalamitaironskarndeposit.(A): Leader: M.Benvenuti Campiglia Marittima mation ofskarnbodies. related apliticdikes (6.2-5.0Ma),aswellthefor- the emplacementofPorto Azzurro intrusionand concentration couldhave preceded(atleastinpart) et al.(2001)suggestthattheprimarystageofiron deposits (Del Tredici, 1990; Torrini, 1990), Tanelli and theresultsobtainedforCalamitaPeninsula titative dataareavailable (cf.Lattanziet al.,1994), the regional framework, forwhichmuchmorequan- (Lippolt etal.,1995).However, takingintoaccount i.e., thesametimespanasPorto Azzurro stock and K/Arageofassociatedadularia,respectively), 0.4 and5.32±0.11Ma(U+ThvsHeageofhematite Terranera andRioMarinadepositfall between6.4± estimates ofthehematite+adulariaassemblagesfrom 1998) arestilllargely unpublished.Radiometricage 1990; SassiNeri:Del Tredici, 1990; Terranera: Seeck, research onspecific deposits(CapoCalamita: Torrini, deposits aremostlyincompleteandresultsofsome understood. Descriptive modelsfortheindividual lage ( 2 kmnorthofCampigliaMarittima() vil- The oredepositsof Valle del Temperino, arelocated Geologic framework (“Campiglia Ridge”)borderedbyhighangleN-Sand described asaN-Strendingwedge-shapedhorst Unit sequencecropoutinthisarea,whichcanbe Fig. 11 ). Several formationsofthe Tuscan long, 1,5kmwideand300mthick(Rodolico,1945; thermometamorphic aureole,approximately5km Massiccio” formation)ismarked byaN-Strending the hostrocks(mainlyrepresentedby“Calcare compositions (Lattanzietal.,2001). The contactwith rocks encounteredindrillholeshave granodioritic ai Marmistockplotinthesyenogranitefield; some Borsi etal.(1967).MostchemicaldatafortheBotro is the“GranitodiBotroaiMarmi”,datedat5.7Maby ic body, croppingoutintheCampiglia Maritimaarea mediate composition. The earliestemplacedmagmat- were emplaced,mostlywithanoverall acidto inter- Several kindsofbothplutonicandvolcanic bodies Marittima areaintheLateMiocene-Lower Pliocene. Magmatic activity stronglyaffected theCampiglia 1967; Costantinietal.,1993;Bossio1993). deposits (Giannini1955;GianniniandLazzarotto, sediments, consistingofalluvium,fluvialandbeach are thenunconformablyoverlain by Quaternary of UpperJurassictoEoceneage. The lattersequences consisting ofcalcareous,marlyandshalyturbidites allochthonous “Ligurian”and“Subligurians”Units, Unit formationsaretectonicallyoverthrust by the gocene turbiditicsandstone(“Macigno”). The Tuscan sic massive limestone(“CalcareMassiccio”)toOli- which belongtothe Tuscan Unit,rangingfromLias- Campiglia Ridgeismadeupofseveral formations, margins, respectively (Acocellaetal.,2000). The NW-SE trendingfaults onthewesternandeastern 24-05-2004, 10:04:12 SKARN DEPOSITS IN SOUTHERN TUSCANY AND ELBA ISLAND CENTRAL ITALY B18

Fig. 11 - Geological map of the Campiglia Marittima district (modified after Tanelli et al., 1993). Key to symbols: (1) Neoautochtonous (Quaternary); (2) Magmatic rocks: quartzmonzonites (γ), quartzlatites (λ), porphyries (π); (3) Ligurian and Subligurian Units; (4) Tuscan Unit (Middle -Oligocene): Posidonomya Marls, , Polichromous Schists, Macigno Sandstone; (5) Tuscan Unit (Lower Jurassic): “Calcare Massiccio” (Massive Limestone) partially metamorphosed to marbles (shaded areas), Reddish Limestone with Ammonites, Cherty Limestones; (6) Tuscan Unit (Lower-Middle? Trias) stratified dolomitic limestomes metamorphosed to grey marbles; (7) ilvaite-hedenbergite skarns (Cu,Pb,Zn±Sn) ; (8) diopside skarns (Cu,Fe±Sn); (9) Fe gossans; (10) supergene (?) Fe oxyhydoxide deposits; (11) Fe oxyhydroxide±cassiterite (supergene/placer) deposits;

Costantini et al., 1993). The dominant calcite-tremo- ferentiate, with intermediate silica contents, high Mg-

lite-diopside skarn assemblage suggests emplacement V (64-71), Ni and Cr, and relatively low Al2O3 and

conditions characterized by temperatures ≤500°C and Na2O contents (Peccerillo et al., 1987). All the fertile pressures ≤1 kb (Barberi et al., 1967). skarn bodies exploited in the Campiglia Marittima Between 5 and 4 Ma, several swarms of porphyry district are closely related to the “Green Porphyry”. B16 to B33 n° 2 - from Volume dikes intruded the eastern part of the Campiglia The “Yellow Porphyry” and the quartz-monzonitic area (Peccerillo et al., 1987). According to Rodolico porphyry are acidic in composition (i.e., very similar (1931) and Barberi et al. (1967), three types of dikes to the the “Botro ai Marmi” intrusion), and display can be distinguished: quartz-, monzonitic a strong potassic alteration. The extensive degree of (also called “Green Porphyry”) and potassic alkaline alteration of the Campiglia porphyry dikes makes it porphyries (“Yellow Porphyry”). The “Green Por- difficult to establish whether the quartz-monzonite phyry” (“Porfido Verde”), also known as “augitic and “yellow” porphyries are both evolved products porphyry”, represents a diopside-bearing mafic dif- from the “Green Porphyry” or represent independ-

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Volume n° 2 - from B16 to B33 B18 - B18 Leader: M.Benvenuti The Valle del Temperino depositsoccurinanarea Green porphyrydikes. sion ofthealreadymentionednetwork of Yellow and more extensive, thoughnotoutcropping,parentintru- the BotroaiMarmigranitestock,but insteadtothe the skarnoresofCampigliaareaarenotrelatedto Botro aiMarmiand/orrelatedintrusions.However, amorphism oftheLiassic“CalcareMassiccio”by enclosed inwhitemarbles,derived fromcontactmet- 4.4 Ma(Ar ing toPinarellietal.,1989)wereeruptedatabout Vincenzo rhyolites(actuallyquartz-latitesaccord- To thenorthofBotroaiMarmiintrusion,San with caution. (1967) fromthe Yellow Porphyry, shouldbeviewed reason, theageof4.3Ma,obtainedbyBorsietal. ent magmas(Peccerilloatal.,1987).For thesame ( the Cu(Pb-Zn)orebodiesfrom Valle del Temperino with galena>sphalerite:e.g.,Cava delPiombo)and area of Valle deiLanzi(predominantPb-Zn,mostly can besubdivided betweenthoseoutcroppinginthe The skarn-sulfide depositsofCampigliaMarittima and rocksarealsominedinthedistrict. intrusion ( minor skarnoccursintheimmediateproximityof tial associationwith(4-5Ma?)porphyrydikes; only E andNEoftheBotroaiMarmistock,instrictspa- Cipriani and Tanelli, 1983). These depositslie1-2km inferred reserves ofabout700,000tons:datafrom at 4%Zn,2%Pb,0.8-1%Cu,and20-70g/t Ag, (with trict wereestimatedtobeintheorderof250,000tons Generale Mineraria”of1975,thereserves inthedis- can timesuptoafew decadesago.Inthe“Relazione al. 1980),whichhave beenexploited sincepre-Etrus- for Cu-Pb-Zn(±Fe,Ag,Sn)skarndeposits(Corsiniet The CampigliaMarittimaareahaslongbeenknown Ore geologyandmineralogy rhyolites. piglia dikes aswellextrusion oftheSan Vincenzo slip lineamentsandprobablycontrolledtheCam- Pliocene extensional tectonicsreactivated thestrike- the emplacementofBotroaiMarmiintrusion. western margin oftheCampigliaRidgefavoured formed duringright-lateralstrike-slip faulting onthe According to Acocella etal.(2000)areleasingbend Ferrara etal.,1989). possible calcalkalineaffinity (Pinarellietal.,1989; amounts ofsubcrustal,mafic-internediate meltof a crustal“anatectic”meltandminorbut significant 1994). They probablyresultedfrommixingbetween Fig. 11 ). Bothskarncomplexes arecompletely Fig. 11 40 /Ar 39 ). A numberofindustrialminerals radiometricage:Feldsteinetal., of about0.4Km ( Porphyry andthemetamorphosedLiassiclimestone ilvaite andhedenbergite occurbetweentheGreen mineralization, namelywithprevailing magnetite, According toCorsinietal.(1980),threezonesof and insmallgossans. als areonlypresentintheupperlevels ofthemines galenobismutinite (Tanelli, 1977).Supergene miner- (traces), arsenopyrite, bismuthinite,mackinawite and rhotite, sphalerite,galena,pyrite, magnetite,hematite Most commonoremineralsincludechalcopyrite, pyr- abundant inassociationwiththe Yellow Porphyry. Silvestro ( gite-johannsenite seriesoccursnearRoccaSan member johannseniteofthesolidsolutionhedenber- and ferroactinolite(Bartholomé&Evrard,1970).End epidote, andtracesofandradite,rhodonite, hedenbergite-johannsenite pyroxene, quartz,calcite, (Table 1;upto9.5wt%MnO,afterRodolico1931), The skarncomplex consistsofmanganoanilvaite and K-feldsparassociation( veinlets bearingthecalcite-epidote-quartz,K-mica the orebodies,andiscrossedbysmallmineralized 12 strictly associatedwiththe“GreenPorphyry” ( southeast elongatedmasses,whichappeartobe del Temperino consistsoftwo west-northwest-east- and Corsinietal.(1980),theskarncomplex of Valle to 50ma.s.l. According toCorsini& Tanelli (1974) if onasmallscale,fromthesurface at250mdown crystals ofmagnetitewithquartzandtracespyrite, of a1mthick,massive aggregate ofcoarsesubhedral deepest levels oftheskarn-sulfide deposit;itconsists Fig. 12 ). The latterseemstobecompletelyembeddedin Figure 12-Schematic crosssectionofthe Valle del ). The magnetitezoneoccursonlyinthe Fig. 13d; Table 1 Temperino deposit(afterCorsinietal.,1980) 2 wherethey have beenmined,even Fig. 13a ). Epidoteisparticularly ). 24-05-2004, 10:04:21 Fig. SKARN DEPOSITS IN SOUTHERN TUSCANY AND ELBA ISLAND CENTRAL ITALY B18

Fig. 13 - Photographs of Campiglia Marittima skarn features: a) The “green porphyry” dike (underground mine gallery, V. Temperino) b) Coarse- grained columnar hedenbergitic pyroxene (underground mine gallery, V. Temperino) c) Sphalerite-rich stope fill from historic mining when Zn was not an economic commodity (underground mine gallery, V. Temperino) d) Johannsenite from Grotta Johannsenite e) Contact between banded johannsenite skarn and marble from Grotta Johannsenite f) Metasomatic banding of Fe-Mn oxyhydroxides and carbonate from Campo alle Buche g) Distal johannsenitic pyroxene vein and dendritic Mn B16 to B33 n° 2 - from Volume oxide veinlets in marble near Rocca San Silvestro h) Distal hydrothermal breccia with near Rocca San Silvestro

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Volume n° 2 - from B16 to B33 B18 - B18 Leader: M.Benvenuti ore assemblageconsistsofchalcopyrite, pyrite, iron- (27.6 wt%MnO)atthecontactwithmarbles. The the coreofskarnbody, toquitepurejohannsenite ed, frommanganoanhedenbergite (2.6wt%MnO)in the Mncontentofclinopyroxene hasbeenrecord- stone sideofthecomplex ( the skarnmineralsweregrowing toward thelime- and enclosedwithintheskarnbodies,showing that with longfibers ( radiating andconcentricaggregates ofclinopyroxene bergite zoneis characterized bothbywell-developed, moles% FeS(Corsiniand Tanelli, 1974). The heden- and hasanironcontentrangingfrom17.2to21.3 ite. Sphaleriteisquitelateinthesulfide paragenesis replaced bytheothersulfides, aswellbymagnet- seems tobeoneoftheearliestmineralphases,andis pseudomorphs afterlamellarhematite.Pyrrhotite sphalerite. Magnetiteoccursheregenerallyonlyas pyrrhotite, withminormagnetite,pyrite andFe-rich typical oreassemblageconsistsofchalcopyrite and directly atthecontactwithGreenPorphyry: the pyrrhotite andchalcopyrite. The ilvaite zoneoccurs of the Valle delTemperino skarn-sulphide(after Corsinietal.1980,Fig. 4) Figure 14-Summarydiagramofthespace-timerelationshipsasshown bythemainminerals Fig. 13b ), andbymarblescorroded Fig. 13e ). An increasein hedenbergite andviceversa, indicates thatthesetwo copyrite andpyrrhotite. The replacementofilvaite by The bandedrockscontainilvaite, hedenbergite, chal- cipitate, followed bysphaleriteand finally by galena. Cu-Pb-Zn sulfides, chalcopyrite beingthefirst topre- place. The thirdstagebroughttothedepositionof stage, crystallizationofilvaite andhedenbergite took a secondgenerationofpyrite (II).Duringthissecond generation (I)was formed,thenpyrrhotite, andthen stage tookplace.Inthesecondstage,afirst pyrite quickly reducedagaintomagnetitebeforethesecond hematite toformatfirst intheouterzones,andtobe changes ofphysicochemicalparametersallowed tion ofironoxides,mainlymagnetite. Temporary stages ( stage process,whichcanbedivided intothreemain (Corsini etal.,1980)appearstohave beenamulti- The oremineraldepositionat Valle del Temperino and andradite. minerals arequartz,calcite,epidote,minorilvaite lamellar magnetiteandhematiteremnants.Gangue poor sphaleriteandfinally ofgalena,withonlyminor Fig. 14 ). The first correspondstothedeposi- 24-05-2004, 10:04:47 SKARN DEPOSITS IN SOUTHERN TUSCANY AND ELBA ISLAND CENTRAL ITALY B18

minerals overlap. noso”), both of them containing evaporites. As mentioned above, absolute age measurements A different type of mineralization, consisting of lay- and the geological reconstruction of the Campiglia ered iron minerals (mainly goethite, hematite, siderite area, indicate a Pliocene age for the formation of the ± marcasite, chlorite) and sparry calcite crystals, with Valle del Temperino skarn-sulfide complex. Regional apparently karstic features, occurs in the old min- stratigraphy indicates that the maximum thickness of ing locality of Campo alle Buche (Fig. 13f). This the sediments over the “Calcare Massiccio” during deposit has been exploited by both underground and the Pliocene was about 1500 to 2000 m (Bartholomé open pit mine workings in the XIX-XX centuries, & Evrard, 1970). Based on mineralogy and S-iso- although there are evidences of older (Etruscan?) tope data Corsini et al. (1980) estimated that sulfide mining activity. According to Bertolani (1958) skarn deposition at Valle del Temperino occurred during sulfide mineralization occurs at some depth below decreasing temperatures from about 400 °C to 250 the calcite-iron oxyhydroxides mineralization. The °C. They also sugget that sources of sulfur for these Campo alle Buche deposit has been regarded as deposits, may have been sulfate (δ34S = 12÷14.6 ‰) a gossan-type ore by early authors (e.g. Ciampi, and/or sulfide (δ34S = 5÷12 ‰) associated with the 1910); alternatively, it can be considered the product /Mesozoic basement formations (namely, of late-stage, low-temperature hydrothermal fluids the “Filladi di ” and/or “Calcare Caver- still related to the Pliocene magmatism which was responsible of the emplacement of the Cu-Pb-Zn(Ag,Sn) skarn bodies of the Campiglia Marittima district (cf. Tanelli, 1977; Tanelli et al., 1992).

A brief review of mining and metallurgy in Etruria Mineraria Mineral resources of Tuscany have long been exploited, at least since Chalcolithic times, and were very important in the development of Etruscan and Roman civilizations; in medieval times, numerous city- states derived important revenues from mining exploitation and metal production. The same applies, on a larger scale, after the unification of Tuscany under the Medici govern- ment in the 16th century. Even in more recent times some mineral resources, such as the Elba iron ore, were successfully exploited. However, despite their economic importance, the archaeology and history of the Tuscan mines has B16 to B33 n° 2 - from Volume not been well studied. Recently, a joint project carried out by the Dipartimento di Scienze della Terra of Firenze and the Dipartimento di Storia Medievale of Siena with

Table 1 Representative electron microprobe analyses of skarn minerals

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Volume n° 2 - from B16 to B33 B18 - B18 Leader: M.Benvenuti area duringthe1 cially, but notexclusively, iron)intheMediterranean A key roleintheproductionandtradeofmetals(espe- by ancientminers. minor occurrences,whichcouldhave beenexploited known mineralresources,frommajordepositsto These studiesprovide adetailedoverview ofall eralogical andhistorical-archaeologicalbackground. 1995), fromthedoubleperspective oftheirgeo-min- Colline Metallifere tant metalproductioncentreduringEtruscan(7 Etruscan town ofPopulonia.Populonia was animpor- (Mascaro etal.,1991)withparticularattentiontothe review ofthemineralresourcesin Tuscany asawhole Regional Government), hasprovided anexhaustive the financial supportofRegione Toscana (Tuscany of Populonia-Baratti (modifiedafterBenvenuti etal.,2000) Figure 15-Sketch mapofthearchaeometallurgical site 40,000m area. The hugeheapsofslags(probablyinexcess of Cu-Pb-Zn-Fe-Ag-Sn oresoftheCampigliaMarittima deposits ofeasternElbaIslandandthepolymetallic its strategic location, midway betweenthelarge iron AD) times.Suchaprominentrolewas mainlydueto century BC)andRoman(2 3 ), discharged alongtheforeshoreofGulf st MillenniumBC,was playedbythe district(CuteroandMascaro, nd centuryBC–1 st century th -3 rd

( the area,particularlyfromslagbeachdeposits coeval) coppermetallurgy canalsobedocumentedin iron production,theexistence ofanearlier(andpartly gical depositsatBaratti-Populoniacanbeascribedto 3 some metallurgical scraps(Campo VI), datingtothe • distinguished, be relatedtodifferent metallurgical steps,have been • the mostlikely sourceareaforsmeltedcopperand, e.g. atMonte Valerio); thelatterdistrictappearstobe Marittima district(whereFe-Snoresarecommon, Elba and,toalesserextent, fromtheCampiglia analyses indicatethatironorescamemainlyfrom content ofsomeironslags: • per, i.e., byaddingunsmeltedcassiteritetorefined cop- data, bronzewas probablyobtainedbycementation, bronze production.Inagreementwitharchaeological Fig. 9g rd two different typesofcopperslags,whichcould trace elementgeochemistry(e.g.,tinanomalous the mineralogicalandcompositionalfeaturesof centuryBCorearlier, provide evidence oflocal ), relationships, morphological, From theanalysisofstratigraphic be brieflysummarizedhere. 2003b, withreferences),andwill (Benvenuti etal.,2000,2003a, have beenpublishedelsewhere The mainresultssofar obtained the EtruscanandRomanperiods. provenance ofsmeltedoresin copper andtin),aswellonthe and non-ferrousmetals(mainly of metallurgical activities foriron establishing thetypesandextent been undertaken, withtheaimof ti beachdeposit: , Campo VI andtheBarat- zone (PoggiodellaPorcareccia, the Populonia-Barattiindustrial four mainexcavation sitesin a detailedresearchprogramon Voss 1988).Inthelasttenyears, half amilliontonnesaccordingto sands tonnesofironbloom(upto iron productionofsomethou- of Baratticoulddocumentatotal • be concluded: cal materialsthefollowing can chemical featuresofmetallurgi- mineralogical, textural, and although mostarcheometallur- Fig. 16a ) andPb-isotope Fig. 15 24-05-2004, 10:04:54 ) has SKARN DEPOSITS IN SOUTHERN TUSCANY AND ELBA ISLAND CENTRAL ITALY B18

possibly, for . Trevisan (1950)’s Complex III rocks, preferentially at the contact between the Rio Marina Formation, or the Field Itinerary Verrucano, and the overlying calcareous levels (“Cal- Elba Island (August 18, 2004) care Cavernoso” Auctt.). According to some authors (cfr. Gillieron, 1959) at Rio Albano the setting of the Stop 1.1: orebodies is structurally controlled. Nevertheless, at The ilvaite-hedenbergite skarn bodies of least in the Valle Giove area, Deschamps et al. (1983) Torre di Rio discovered a pyrite-bearing horizon within Verru- The area is characterized by a NW-plunging sequence cano Fm. (“Schistes verts minéralisés”), which they of marbles and calc-schists (Fig. 9e) of variable size interpreted as a relic (syngenetic) of an iron protore. with minor grey/greenish quartzitic phyllites. They In the Rio Marina and Rio Albano deposits hematite belong to the Acquadolce Unit of Bortolotti et al. (“specularite”) is the main ore mineral which may (2001). Syn-metamorphic tight to isoclinal folds with show either a typical lamellar-micaceous habits or a pervasive axial plane schistosity are well exposed. flattened, rhombohedral crystals, often covered by Deino et al. (1992) obtained a 40Ar/39Ar radiomet- iridescent films of iron hydroxides. Pyrite is also ric age of 19-20 Ma for this schistosity. A 1-metre common, predominantly as pyritohedra, although thick, grey/whitish calc-schist level is well exposed octahedra or cubes have been observed as well. Exog- along the road. Moving southwards from the Appi- enous limonites, in massive or concretionary (some- ani Clock-Tower and along the coast, we can easily times stalactitic) forms may locally constitute the observe the gradational passage from calc-schists to main ore minerals, especially at Rio Albano and other the hedenbergite-ilvaite-epidote skarn bodies. Skarn mineral showings to the north. It should be noted that bodies consist of almost monomineralic masses of in the 1950’s-60’s underground mine workings partly garnet-epidote, hedenbergitic pyroxene and ilvaite exploited a hematite+pyrite orebody associated with (Fig. 9b), with associated quartz, chlorite and minor skarn silicates, known in the literature as “Rio Marina amounts of iron minerals (magnetite, pyrite and pyr- profondo” (= Rio Marina deep body”). rhotite), which justified limited exploitation activity in the past. Mesoscale textures clearly indicate that Stop 1.3: the replacement of minerals in the calc-schists by Along the Calamita mine road skarn minerals, occurred preferentially along the After leaving , we pass by the tectonic con- schistosity planes of the original rock, as pointed out tact between the Flysch Unit and the Porto Azzurro by Lotti (1886,pp. 205-206). Ilvaite is here exception- Unit, constituted by Mt. Calamita Fm. (Palaeozoic ally abundant (Fig. 9d): it occurs in beautiful, centi- grey to brown micaschists, phyllites and quartzites metric black, prismatic crystals, with typical vertical locally intruded by aplitic dikes) and the Barabarca striae and submetallic lustre. This is the type locality Fm. quartzites (Middle-Late Triassic). Just above the where ilvaite (so called after the Latin name of Elba sea-village of Pareti (down the cliff) we can observe Island: “Ilva”) was first discovered and described in along the road some lenticular dark green bodies 1802 (Franchini et al., 2002). of (tremolite + andesinic plagioclase + chlorite ± sphene, apatite) which Puxeddu et al. Stop 1.2: (1984) referred to WPB metabasites. We finally reach The Rio Marina mining area the former Calamita Mine Headquarters (“Palazzo”), (seen from Torre di Rio) which is one of several open pit and underground Fe Looking from the Appiani clock-tower to the NW, mines along the coast (Fig. 9a). the landscape is dominated by the Rio Marina mines (from the left: Bacino, Zuccoletto, Valle Giove and Stop 1.4: B16 to B33 n° 2 - from Volume Vigneria mines) and by the Torre del Giove hill (351 The Calamita mine: northern stopes m), with the ruins of a castle of the XVIth century. In this area thermometamorphic carbonate rocks The Rio Marina ores are hosted in the Permo-Car- occur. They consist mainly of stratified dolostones boniferous (Rio Marina Fm.) and in the Triassic and dolomitic limestones, grey-whitish in colour, Verrucano Auctt.) metasiliciclastics of the Monti- with rare phyllitic intercalations (Late Triassic?). To ciano-Roccastrada Unit. The iron deposits of Rio the east, along the road, there are outcrops of whitish Marina (as well as Rio Albano, to the north) consist saccharoid marbles (Hettangian?), massive or poorly of stratiform, massive or vein-like bodies, hosted by stratified, with local grey dolomitic levels. These car-

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Volume n° 2 - from B16 to B33 B18 - B18 Leader: M.Benvenuti “organic” mineralslike minguzzite(K have beenreported. At Vallone Alto, moreover, rare of malachite,azurite,atacamite,paratacamite,etc. Cave) site,justbelow theU-shapedtrench,veinlets magnetite. At theso-called“GrottaRame”(=Copper were subsequentlyexploited almostexclusively for involved thelimoniticgossanofironores,which beginning ofthepastcenturyproductionmainly main stopes(Vallone Bassoand Vallone Alto). At the easily visiblefromthemineroadseparatestwo 112 m.a.s.l.),excavated inthemetacarbonatesand (Punta dellaCalamita). A U-shapedtrench(altitude: of whichcanbeobserved justontheseaward cliffs hedenbergite-ilvaite skarnbodies,beautifulexamples focussed onseveral magnetitelensesassociatedwith visited duringthisfield trip)theexploitation activity In thesouthernstopesofCalamitaMine(nottobe (Torrini, 1990). between thegarnetskarnandmagnetitelenses chalcantite, etc.)werelocallyexploited atthecontact (pyrrhotite, pyrite, chalcopyrite ±malachite,azurrite, nite andpyrite. Moreover, massesofFe-Cusulfides amounts ofsphalerite,chalcocite,arsenopyrite, bor- tite). Additional phasesincludegoethiteandtrace massive bodiesofmagnetite(±kenomagnetite, hema- skarns describedabove, andconsisted oflensesand exploited oreswereassociatedwithbothtypesof etta, Albaroccia, Macei,Polveraio, CotiNere. The is subdivided intoseveral mine-working areas:Civ- magnitude. The northernsectoroftheCalamitaMine iron reserves ofapproximatelythesameorder in theperiod1860-1920byopenpitmining,with least 2milliontonnesofironorehadbeenexploited Etruscan?-Roman times;accordingtoPullé(1921)at Mining activity atCalamitaprobablydatesbackto (Meinert 1992,1995,1997). zones ( the proximalsouthwesttopyroxene-ilvaite indistal Calamita Fm. The skarniszonedfromgarnet-richin tact betweenmetacarbonatesandtheunderlyingMt. (Torrini, 1990).Skarnbodiesmainlyoccuratthecon- most abundant, andanilvaite-hedenbergite skarn skarn: agarnet(andradite)-skarn,quantitatively the which ledtothedevelopment oftwo maintypesof latter have beenaffected byextensive metasomatism, the Mt.CalamitaFm.andcarbonaterocks. The the quartzitesofBarabarcaFm.occurbetween zoic cover oftheMt.CalamitaFm.:moretowest, bonate rocksmayrepresentpartoftheoriginalMeso- by Cocco,Garavelli (1954). H 2 O) andoxalite(FeC Fig. 9c,f ), asistypicalofmostskarnsystems 2 O 4 · 2H 2 O) have beenreported 3 Fe(C 2 O 4 ) 3 ·3 Campiglia Marittimadistrict(August 19,2004) abundant concentrationsofepidotealsooccur. veins. ( tures like ahydrothermalbrecciaandsmallMn-oxide envelopes ( an outcropofthe“Yellow Porphyry”,withthinskarn road tothelimestonequarries,itispossibleobserve At thebaseofRoccaSanSilvestro, alonganinternal granite inthebackground. working inthelocalmines),withBotroaiMarmi from thegerman can enjoy thepanoramaof Valle deLanzi(Lanzi= in thisarea.FromthetopofRoccaSanSilvestro one and , derived fromtheearlymetallurgical works found alsosomeremnantsandslagswithcopper, lead als fromshallow skarnsandgossans.Herehave been medieval villagebuilt aroundtheminingofbasemet- We willstarttheascenttoRoccaSanSilvestro, anold nearby hydrothermal breccia vestro; “Yellow Dike” with skarn envelope and Valle deiLanzi. View from theRoccaSan Sil- Stop 2.1: whole area. books onthisthemeandthefauna andfloraofthe in asmall,but wellorganized shoparesoldseveral the miningdistrictsarealsoamongexhibits and taken fromtheCu-andZn-Pbmines.Oldmapsof contains somespectacularmineralogicalsamples ogy, mineralogyandmininghistoryofthisarea Temperino. The Museumisdedicatedtothegeol- set upinoneoftheoldminebuildings at Valle del We willvisitthesmall,but very interestingMuseum, Mineral Museumof Valle del Temperino Stop 2.3: Massiccio” contactmetamorphism( bands, replacingthemarblesderived from“Calcare of Johannseniteoccurringaspinkishrosettesand very fine specimens(donothammertheoutcrop!!!) ( (walk) totheclassicallocalityofGrottaJohannsenite From theupperpartof Valle deiLanzi,wedrive Grotta Johannsenite (Gallerione) Stop 2.2: solution. members ofthehedenbergite-johannsenite solid assemblage andrepresentshereoneoftheend- Mn-pyroxene isatypicalcomponentoftheZn-skarn Fig. 11 Fig. 13h ). Herewecanobserve theoccurrenceof Fig. 13g ) Around the“Yellow Porphyry”, Landsknechte ), aswelldistalalterationfea- , whowereattimes Fig. 13d,e 24-05-2004, 10:05:01 ). This SKARN DEPOSITS IN SOUTHERN TUSCANY AND ELBA ISLAND CENTRAL ITALY B18

Stop 2.4: Underground Mine Valle del Temperino: Green Dike and Hedenbergite skarn This Stop will take us underground in one mine gal- lery of the copper mine of Valle del Temperino. The mine is not active anymore, having been converted into a popular tourist attraction, and it’s walls show the characteristic green patina of supergene copper minerals.. Nevertheless, there are still many interest- ing sites in the mine where geologists can observe the geological occurrence of the “Green Porphyry Dike” (Fig. 13a) thought to be genetically associ- ated with mineralization, the marble host rocks, and

Figure 17 - Location of the principal mine workings at Calamita Mine (after Calanchi et al., 1976). Legend: 1. Civetta; 2. Albaroccia; 3. Nuova Zona; 4. Macei Alto; 5. Polverio; 6. Coti Nere; 7. Le Piane; 8. Punta Rossa; 9. Macei Basso; 10. Vallone Alto; 11. Vallone Basso. hedenbergite skarns (Fig. 13b) with sphalerite and chalcopyrite. It is interesting to note that many of the old workings were backfilled with high grade Zn-ore, also occurring in the skarn, which was not economic in pre-industrial times (Fig. 13c). Stop 2.5: Mn-vein outcrops near mine exit along road to the “Gran Cava” pyroxene locality Out of the underground adit, we walk up a small mine road characterized by interesting exposures of distal Mn-oxide veins and internal sediment-filled frac- tures, as well by hydrothermal breccias that directly overlie the underground ores. Such distal alteration features are common in the periphery of most skarn districts in the world. The road will bring us to the

Figure 16 - Photomicrographs of archaeometallurgical “Gran Cava”, a small open pit also known as “Cava B16 to B33 n° 2 - from Volume samples from Populonia-Baratti: a) Backscattered Etrusca”, so called because it is thought to have been electron image of partially smelted mineral charge exploited already in Etruscan times. There we will showing micrometric globules of Fe-Sn phases (white), observe coarse-grained hedenbergite pyroxenes and sometimes surrounded by Fe-S phases. The groundmass a well-exposed skarn-marble contact. is composed of a glassy matrix and acicular crystals of hedenbergitic composition. Bar = 10 µm. b) Reflected light image of sulphidic droplets in (type-A) copper slags. Stop 2.6: Abbreviations: cc = chalcosite-djurleite; cv = covellite. Fe-Oxides at Campo alle Buche Width of field: about 500 µm. Our last outcrop is situated at the westernmost

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Volume n° 2 - from B16 to B33 B18 - B18 Leader: M.Benvenuti the twentiethcentury. The mineralizedlithotypecon- was exploited forironoreuntiltheearlydecadesof of “CampoalleBuche”=literally“field withholes” with aNNE-SSWtrendingfault. The oldminingarea extremity oftheCampigliaarea,incloseproximity (modified afterCorsiniandTanelli, 1974) Temperino depositarea Figure 18-Schematic geologic mapofthe Valle del Figure 19-Proposedreconstruction of EtruscanironfurnacesfromBaratti(afterBenvenuti etal.,2003b). venuti etal.,2000). Type-A types ofcopperslags:type-Aandtype-Bslags(Ben- beach slagdepositledtotherecognitionoftwo main on theirsurfaces. PreliminaryanalysesoftheBaratti spots (duetoexogenous alterationofcoppersulfides) copper slags,clearlyidentifiable bythegreenish bottom portionofthedepositmostlyconsists (August 19,2004) The archaeometallurgical siteofPopulonia-Baratti that wereassociatedwithskarnformation. dizing environment, ofthesamehydrothermalfluids probably representsthedistalproduct,inamoreoxi- pi,. 1910). The CampoalleBuchemineralization as gossan-like depositsbyearlyauthors(e.g.Ciam- chalcocite/dijenite) (see copper oxides(cuprite)andsulphides(covellite, droplets, mostlyfine aggregates ofmetalliccopper, magnetite, andminorglass,withabundant metallic ized byagroundmassofdominantolivine, pyroxene, chlorite) withcalcitecrystals( als (mainlygoethite,hematite,siderite±marcasite, sists hereofalternatingbandslaminatedFeminer- discharged over anerosionalterrace poorly cementedheapofEtruscanandRomanslags in ordertoobserve theremainsofslagdeposit,a gico diBaratti. We leave thebus andreachthebeach the roadtoPopulonia. We entertheParco Archeolo- district, wemove backtowards ,andtake At theendofourvisittoCampigliaMarittima The beachslagdepositatBaratti Stop 2.7: Fig. 16b copper slagsarecharacter- Fig. 13f ). Intype-Bcopper

( Fig. 9g ). Interpreted 11-06-2004, 7:58:33 ). The SKARN DEPOSITS IN SOUTHERN TUSCANY AND ELBA ISLAND CENTRAL ITALY B18

slags magnetite and cuprite are much less abundant, Bibliography metallic copper is consistently absent, and the metal- ABBATE E., BORTOLOTTI V., PRINCIPI G. (1980) lic globules (100-150µm in size) are mainly copper- – Apennine : a peculiar oceanic crust. In: iron-sulphur phases (matte) showing fine exsolution Rocci, G. (ed), Tethyan Ophiolites, Western Area, textures. These features could indicate a multi-stage Ofioliti, Spec. Issue, vol.1, 5-96. copper smelting process, with type-B slags belong- BARBERI F., INNOCENTI F., MAZZUOLI R. ing to an earlier (matte production) stage than type-A (1967) – Contributo alla conoscenza chimico-petro- slags. grafica e magmatologica delle rocce intrusive, vulca- The largest portion of the slag deposit consists of iron niche e filoniane del Campigliese (Toscana). Mem. slags of different kinds (furnace slags, tapped slags, Soc. Geol. It., 6, 643-681. furnace conglomerates). The iron slags are mainly a BARTHOLOMÈ P., EVRARD P. (1970) – On the silicate groundmass of fayalitic olivine (with up to genesis of the zoned skarn complex at Temperino, 1.45% CaO) in an iron-rich interstitial glassy matrix Tuscany. In: Problems of hydrothermal ore deposi- (up to c25 wt.% FeO), which in itself is normally a tion; the origin, evolution, and control of ore-forming eutectic of anorthite and fayalite. Wüstite, magnetite, fluids. I.U.G.S., Series A(2), Stuttgart, 53-57. hercynite and partially smelted, relic phases like BENVENUTI M., CHIARANTINI L., NORFINI quartz, hematite and scheelite (?), occur in variable L., CASINI A., GUIDERI S., TANELLI G. (2003a) amounts, and are especially abundant in furnace - The “Etruscan tin”: a preliminary contribution slags. Fayalite crystals in tapped slags occur as from researches at Monte Valerio and Baratti- small laths associated with micrometric dendrites of Populonia (southern Tuscany, Italy). Colloqium on wüstite, while in furnace slags both minerals show a «Archéométallurgie: le problème de l’étain à l’origine significant increase in size. Unlike tapped and furnace de la métallurgie », XIV Congr. U.I.S.S.P., Liège, 2- slags, furnace conglomerates show abundant relics of 8 septembre 2001, Archeopress, BAR [in press]. hematite and quartz and a more silica-rich (and FeO- BENVENUTI M., MASCARO I., COSTAGLIOLA poor) glassy groundmass. Iron slags almost invariably P., TANELLI G., ROMUALDI A. (2000) – Iron, contain droplets of metallic iron. Some iron slags are copper and tin at Baratti (Populonia): smelting pro- enriched in tin and may contain micrometric globules cesses and metal provenances. Historical Metallurgy,

of iron-tin alloys, approximating FeSn and FeSn2 in Historical Metallurgy Soc. Ed., London, England, 34 composition (Fig. 16a). (2), 67-76. Fragments of smelting furnaces are also commonly BENVENUTI M., MORELLI F., CORSINI F., present in the Baratti beach deposit. They are made MASOTTI A., LATTANZI P., TANELLI G. (1994) up of local Macigno sandstone and baked clay, possi- - New isotopic data on the pyrite (±Cu-Pb-Zn) deposit bly derived from the terrigenous Canetolo formation of Campiano (southern Tuscany). Mem. Soc. Geol. (see Fig. 18). The baked clays show characteristic It., 48, 691-697. colour zoning from red to black, corresponding to BENVENUTI M., PECCHIONI E., CHIARANTINI increasing reducing atmosphere and temperatures in L., CHIAVERINI J., MARIANI A., MASCARO the furnaces. The reconstruction of Etruscan (and/or I. (2003b) - An investigation on iron smelting fur- Roman?) iron furnaces proposed by Benvenuti et al. naces from the Etruscan site of Baratti-Populonia (2003b) is shown in Fig. 19. (Tuscany). Proceedings Volume of the 6th Int. Con- If time permits, we will visit some of the Etruscan gress on Ancient Ceramics (EMAC ’01), Fribourg tombs located in the nearby archeological site. (Svizzera), 3-6 Ottobre 2001 (in press). BOCCALETTI M., GUAZZONE G. (1974) – Rem- nant arcs and marginal basins in the Cainozoic devel- Volume n° 2 - from B16 to B33 n° 2 - from Volume opment of the Mediterranean. Nature, 252, 18-21. BONINI M., BOCCALETTI M., MORATTI G., SANI F. (2001) – Neogene crustal shortening and basin evolution in Tuscany (Northern Apennines). Ofioliti 26 (2a), 275-286. BORSI S., FERRARA G. & TONGIORGI E. (1967) – Determinazioni con il metodo K/Ar dell’ età delle rocce magmatiche della Toscana. Boll. Soc. Geol.

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Volume n° 2 - from B16 to B33 B18 - B18 Leader: M.Benvenuti TAVARNELLI E.,ELTER F.M. (1993)–Geologia CANTELLI M.,MAZZANTIR.,SANDRELLIF., COSTANTINILAZZAROTTOMAC- A., A., 30: 337-345. Alps (northern Tuscany, Italy).Mem.Soc.Geol.It., - Barite-ironoxides-pyrite depositsfrom Apuane CORTECCI G., LATTANZI P., TANELLI G.(1985) Marittima, Tuscany, Italy. Econ.Geol.,75,83-96. Zn) sulfide depositof Valle del Temperino, Campiglia G. (1980)-Sulfurisotopestudyoftheskarn-(Cu-Pb- CORSINI F., CORTECCI G.,LEONE TANELLI 30, 205-221. Toscana). Rend.Soc.ItalianaMineralogiaPetrologia, della Valle del Temperino (CampigliaMarittima, microsonda elettronicadelleblendedelgiacimento CORSINI F. & TANELLI G.(1974)– Analisi alla terranean Archaeology, vol. 14.,127-145. of NaturalHistoryinGeneva, 4-7June,1999,Medi- of Africa andtheMediterraneanBasin, The Museum First InternationalColloquiumon The Archaeology reference to beginning ofironmetallurgy in Tuscany; withspecial CORRETTI A., BENVENUTIM.(2001)- The 10: 269-350. ferro diCapoCalamita(Elba).Rend.Soc.Miner. It., alcuni problemigeochimicirelativi algiacimentodi COCCO G.,GARAVELLI C.(1954)-Studiodi Appennine. Nature,276:604-605. tic magmatismduetoanticlockwiserotationofthe (1978) -Eastward migrationsofthe Tuscan anatec- CIVETTA L.,ORSIG.,SCANDONEP., PECER. Firenze. Acc. Tosc. Sc.Lett.“LaColombaria”,48:241-283, rarie della Toscana: notestoricheedeconomiche CIPRIANI C., TANELLI G.(1983)-Lerisorsemine- 29 (1),156-164. sulle limonitidelCampigliese.Boll.Soc.Geol.It., CIAMPI A. (1910)– Alcune recentiosservazioni 102 pp. – Miniereemineralidell’Elbaorientale.Bologna, CALANCHI N.,DAL RIOG.,PRATI A. (1976) 17-98. del Neoautoctono Toscano. Mem.Soc.Geol.It.,49, (1993) –Rassegna delleconoscenzesullastratigrafia MAZZEI R.,SALVATORINI G.,SANDRELLIF. LAZZAROTTO A., LIOTTA D.,MAZZANTIR., L.M., COSTANTINIFORESI BOSSIO A., A., Ofioliti geology oftheCentralandEasternElbaIsland,Italy. PRINCIPI G.BABBINI A., CORTI S.(2001)- The BORTOLOTTI V., FAZZUOLI M.,PANDELI E., Italiana, 86,403-410. 26 (2a),97-150. Etruria Mineraria . Proceedingsofthe .

G. (1992)-Datazioni DEINO A., KELLERJ.V.A., MINELLIG.,PIALLI Geol. It.,74:53-85. che nellezoneminerariedell’isolad’Elba.Boll.Serv. DEBENEDETTI A. (1952)-Osservazioni geologi- Firenze. ralogico: aspettinaturalisticiestorico-archeologici, lifere. Inventario delpatrimoniominerarioemine- CUTERO F., MASCARO I.(1995)-CollineMetal- Suppl. n.2,1-164. Quaderni MuseoStoriaNaturaleLivorno, Vol. 13, della provincia diLivorno aSuddelfiume Cecina. FERRARA G., TONARINI S.(1985)-Radiometric nol., 51,379-388. San Vincenzo rhyolites(Tuscany, Italy).Bull. Volca- S. (1989)–Petrologyandisotopegeochemistryof FERRARA G.,PETRINIR.,SERRI TONARINI 943-958. 58, Cosmochim. Acta, rhyolite, San Vincenzo, Tuscany (Italy).Geochim. microsampling constraintsonthehistoryofaS-type G.R., HALLC.M.(1994)–Isotopeandchemical FELDSTEIN S.N.,HALLIDAY A.N., DAVIES 162 pp. dell’Isola d’Elba.Mem.Descr. CartaGeol.It.,11, FABRI A. (1887)-Relazionesulleminierediferro Volume: 317-391. (1981) -Skarndeposits.In:Econ.Geol.75° Anniv. EINAUDI M.,MEINERT L.D.,NEWBBERRY R.J. S.276. 65, (TGA), A, tectonics. TübingerGeowissenschaftliche Arbeiten ore depositsandtheirinterrelationwithMessinian DÜNKEL, I.(2002)- The genesisofEastElbairon 139(3), 257-279. granitic complex ofElbaIsland,Italy. Geol.Mag., evolution ofthelateMiocenelaccolith-pluton-dike S., WESTERMAN D.S. (2002) - The magmatic DINI A., INNOCENTIF., ROCCHI S., TONARINI Dep., 6,356-379. et lesskarnsduGinevro (Iled’Elbe–Italie).Mineral. DIMANCHE F. (1971)-Lesmineraisdemagnetite Schweiz. Mineral.Petr. Mitt.,63:149-165. connaissance desgisementsde Toscane- I.Partie 1. (Rio Marina,Iled’ Elbe,Italie).Contribution àla - Legisementdepyrite-hématite de Valle Giove J, MARIGNAC C.,MAINEB.,SAUPÉ F. (1983) DESCHAMPS Y., DAGALLIER G.,MACAUDIER sis, Università diFirenze,200pp. skarn diSassiNeri(Isolad’Elba).Unpublished The- DEL TREDICI F. (1990)-Studiodelgiacimentoa 1A, Vol. Spec.1992/2:187-192. risultati preliminari.StudiGeol.Camerti,CROP 1- dell’Unità diOrtano-RioMarina(Isolad’ Elba): 40 Ar/ 39 Ar delmetamorfismo 24-05-2004, 10:05:18 SKARN DEPOSITS IN SOUTHERN TUSCANY AND ELBA ISLAND CENTRAL ITALY B18

geochronology in Tuscany: results and problems. tion of mineral deposits in southern Tuscany, Italy. Rend. Soc. It. Mineral, Petrol., 40, 111-124. In: M. Pagel and J.L. Leroy (Eds), Source, Transport Franchini, M.B., Meinert, L. D., and Vallés, J.M., and deposition of metals. Proceedings of the 25 years 2002, First occurrence of ilvaite in a Au skarn SGA Anniversary Meeeting, Balkema, Rotterdam: deposit: Economic Geology, v. 97, p. 1119-1126. 317-320 GIANNINI E. (1955) – Geologia dei Monti di Cam- LIPPOLT, H.J., WERNICKE, R.S., BÄHR, R. (1995) piglia Marittima (Livorno). Boll. Soc. Geol. It., 84, - Paragenetic specularite and adularia, Elba Island, 1-77. Italy: Concordant, U+Th-He and K-Ar ages. Earth GIANNINI E., LAZZAROTTO A. (1967) – Studi Planet.Sci.Lett., 132: 43 – 51. geologici di una sezione tra i monti di Campiglia LOTTI B. (1886) - Descrizione geologica dell’isola Marittima e la parte centromeridionale dei Monti d’Elba. Mem. Descr. Carta Geol. d’ Italia, 2, 254 pp. del Chianti. Atti Soc. Tosc. Sc. Nat. Mem., Ser. A, MAINERI C., BENVENUTI M., COSTAGLIOLA 78-101. P., DINI A., LATTANZI P., RUGGIERI G., VILLA GILLIERON F. (1959) - Osservazioni sulla geologia I. (2003) - Alkali-metasomatic processes at La Cro- dei giacimenti di ferro dell’Elba orientale. L’Ind. cetta raw ceramic material mine (Elba Island, Italy): Miner., X (1), 1-10. interplay between magmatism, tectonics and minera- JUTEAU M., MICHARD A., ALBAREDE F. (1986) lization. Mineral. Deposita, Springer-Verlag, Berlin- - The Pb-Sr-Nd isotope geochemistry of some recent Heidelberg, 38, 67-86. circum-Mediterranean granites. Contrib. Mineral. MARINELLI G. (1975) - Magma evolution in Italy. Petrol., 92: 331-340. In: C.H. Squyres (Ed.), Geology of Italy. Earth Sci. KELLER J.V.A., PIALLI G. (1990) - Tectonics of Soc. Libyan Arab Republic, Tripoli, p. 165-219. the Island of Elba: a reappraisal. Boll. Soc. Geol. It., MASCARO I., GUIDERI S., BENVENUTI M. 109: 413-425. (1991) – Inventario del patrimonio minerario e mine- LATTANZI P. (1999) - Epithermal precious metal ralogico in Toscana. Aspetti naturalistici e storico- deposits of Italy: an overview. Mineralium Deposita, archeologici, Firenze, Ed. Regione Toscana, 2 vv. 34, 630-638. Meinert, L.D., 1992, Skarns and skarn deposits: LATTANZI P., BENVENUTI M., COSTAGLIOLA Geoscience Canada, v. 19, p. 145-162. P., MAINERI C., MASCARO I., TANELLI G., Meinert, L.D., 1995, Compositional variation of DINI A., RUGGIERI G. (2001) - Magmatic versus igneous rocks associated with skarn deposits - hydrothermal processes in the formation of raw cera- Chemical evidence for a genetic connection between mic material deposits in southern Tuscany. Proceed- petrogenesis and mineralization: in Thompson, ings 10th Int. Symposium on Water-Rock Interaction, J.F.H., ed., Magmas, fluids, and ore deposits, Min. Villasinius (Italy), 10-15 June 2001, 725-728. Assoc. Can. Short Course Series, v. 23, p. 401-418. LATTANZI P., BENVENUTI M., COSTAGLIOLA Meinert, L.D., 1997, Application of skarn deposit P., TANELLI G. (1994) - An overview on recent zonation models to mineral exploration: Exploration research on the metallogeny of Tuscany, with special and Mining Geology, v. 6, p. 185-208. reference to the Apuane Alps. Mem. Soc. Geol. It., 48 PECCERILLO A. (1999) - Multiple mantle metaso- (1992): 613-625, 6 figg., 2 tavv., Roma. matism in central-: geochemical effects, LATTANZI P., BENVENUTI M., GALE N.H., timing and geodynamic interpretations. Geology, 27: HANSMANN W., KOEPPEL V., STOS-GALE Z. 315-318. (1997) - Pb-isotope data on ore deposits of Southern PECCERILLO A., CONTICELLI S., MANETTI P. Tuscany. Plinius, 18: 123-124. (1987) - Petrological characteristics and the genesis LATTANZI P., TANELLI G. (1985) - Le mineralizza- of the recent magmatism of Southern Tuscany and zioni a pirite, ossidi di Fe e Pb-Zn(Ag) della zona di Northern Latium. Period. Mineral., 56, 157-172. B16 to B33 n° 2 - from Volume Niccioleta (). Rend. S.I.M.P., 40: 385-408. PECCERILLO A., POLI G., DONATI C. (2001) LATTANZI P.F., HANSMANN W., KOEPPEL V., - The Plio-Quaternary magmatism of southern Tus- COSTAGLIOLA P. (1992) - Source of metals in cany and northern Latium: compositional character- metamorphic ore-forming processes in the Apuane istics, genesis and geodynamic significance. Ofioliti, Alps (NW Tuscany, Italy): constraints by Pb-isotope 26 (2a), 229-238. data. Mineral. and Petrol., 45: 217-229. PERTUSATI P.C., RAGGI G., RICCI C.A., DURAN- LATTANZI, P., HANSMANN, W., KOEPPEL, V. TI S., PALMERI R. (1993) - Evoluzione post-colli- (1991) - Preliminary data on the Pb-isotope composi- sionale dell’Elba centro-orientale. Mem. Soc. Geol.

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Volume n° 2 - from B16 to B33 B18 - B18 Leader: M.Benvenuti Mem. Soc.Geol.It.,31:299-304. and mineralexploration in Tuscany: stateoftheart. TANELLI G,LATTANZI P. (1986)-Metallogeny Tübingen. Diplomkartierung, Eberhard-Karls-Universität geologischer Rahmen.Diplomarbeitund Laghetto di Terra NeraaufOstelbaundderen SEECK I.(1998)-DieGenesederEisenerzlagerstätte Italie). Bull.Mineral.,105,236-245. partie orientaledel’ iled’Elbe(Province deLivourne, methodes K/AretRb/Srdequelquesrochesla J., ZIMMERMANJ.L.(1982)-Datationparles SAUPÉ F., MARIGNAC C.,MOINE B.,SONET 554. applied tooredeposits,Balkema, Granada,p.551- and F. Gervilla(Eds.),CurrentResearchingeology Campigliola. In:P. FenollHach-Ali,J. Torres-Ruiz southern Tuscany: theexamples ofFrassineandLa – Carbonate-hostedepithermalgoldmineralizationin RUGGIERI G.,LATTANZI P., TANELLI G.(1993) Campigliese. Atti Soc. Tosc. Sc.Nat.,52,125-132. RODOLICO F. (1945)–Ragguagli sul granitodel 132. fiche sull’ilvaite. PeriodicodiMineralogia,2,122- RODOLICO F. (1931)–Osservazioni cristallogra- 77-113. the oredepositsof Tuscany, II).Chem.Geol.,43, of Tuscany, Italy(contribution totheknowledge of investigation ofgeothermalandmineralresources and stratigraphiccorrelations. Application tothe GIANELLI G.,MOINEB.(1984)-Geochemistry PUXEDDU M.,SAUPÉ F., DECHOMETSR., Torino, p.181-259. Stella (Ed.),Leminierediferrodell’Italia,Lattes, PULLÈ G.(1921)-Leminieredell’Elba.In: A. Soc. Geol.It.,28,549-576. problema generaledellimite Alpi-Appennini. Mem. Appenninico comeprismadiaccrezione.Riflessisul PRINCIPI G., TREVES B.(1984)-IlsistemaCorso- J. Geol.,100,41-56. and accessoryphasescrystallisationintheirgenesis. ago Granitoids,CentralItaly:theroleofhybridisation POLI G.(1992)-Geochemistryof Tuscan Archypel- Mineralogia, 58,67-96. Roccastrada andSan Vincenzo centers.Periodicodi the Tuscan magmaticprovince (CentralItaly):the chemical characterizationofrecentvolcanism from PINARELLI L.,POLIG.,SANTO A. (1989)–Geo- It., 49:223-312. Mem. LinceiSc.Fis.Nat.,SerieIX,1(4):97-128. Island (Italy):remarksforametallogenicdiscussion. ZUFFARDI P. (1990) - The irondeposits oftheElba B, 22:591-732. Zeitschrift derDeutschengeologischenGesellschaft., mineralogische FragmenteausItalien.III Theil. VOM RATH G. (1870)-DieInselElba.Geognostich- Contrib. Mineral.Petrol.,60:109-118. relations betweenacidandalkalinerocksinItaly. VOLLMER R.(1977)-Isotopicevidence forgenetic Univ. Padova., 16:5-39. tonica discivolamento pergravità. Mem.Ist.Geol.. TREVISAN L.(1950)-L’Elba orientaleelasuatet- Firenze, 163pp. settentrionali). Unpublished Thesis, Università di e magnetitediCapoCalamita,Isolad’Elba(cantieri TORRINI G.(1990) -Studiodelgiacimentoaskarn 3rd Series,11(2):1-9. fere della Toscana meridionale.L’Industria mineraria, modellizzazione geneticadellemineralizzazioniauri- TANELLI G.,SCARSELLA A. (1990)– Tipologia e 715-728. tali, culturalieindustriali”.Boll.Soc.Geol.It.,112, (1993). ImineralidelCampigliese:“Beniambien- TANELLI G.,MORELLIF. &BENVENUTIM. ma, Rotterdam,p.109-114. Italy. In:E.A.Ladeira(Ed.).Brazil Gold’91,Balke- SINI F. (1991)-Metallogeny ofgoldin Tuscany, TANELLI G.,LATTANZI P., RUGGIERI G.,COR- 248. of ElbaIsland:statetheart.Ofioliti P., RUGGIERI G.(2001)- The ironmineral deposits DINI A., MAINERIC.,MASCARO I.,LATTANZI TANELLI G.,BENVENUTIM.,COSTAGLIOLA P., May 1996,465-470. Vol. LIV, Memorie Descrittive delServizioGeologicod’Italia, tional tooltowards thegrowth ofa“geologicculture”. of anoutstandingheritageanditsuseaseduca- and minesfromElbaIsland(Italy):conservation TANELLI G.,BENVENUTIM.(1999)-Minerals 91-109. e minerogenesiin Toscana. Mem.Soc.Geol.It.,25: TANELLI G.(1983)-Mineralizzazionimetallifere 903. Toscana. Rend.Soc.It.Mineral.Petrol.,33(2),875- TANELLI G.(1977)-Igiacimentiaskarndella Atti IIndInt.Symp.ProGEO , Rome,20-22

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