MINERALS of the METAMORPHOSED Mn-Fe DEPOSITS in ROMANIA: OLD DEPOSITS, NEW SPECIES

Acta Mineralogica-Petrographica, Abstract Series 1, Szeged, 2003

MINERALS OF THE METAMORPHOSED Mn-Fe DEPOSITS IN ROMANIA: OLD DEPOSITS, NEW SPECIES

HÎRTOPANU, P.1, UDUBAŞA, G.1 & SCOTT, P.2 1 Geological Institute of Romania, Caransebeş 1, RO-78344 Bucharest, Romania. E-mail: [email protected] 2 Camborne School of Mines, Redruth, Cornwall, United Kingdom.

The main metamorphosed Mn-Fe deposits in Romania pore, groutite, etc. V. Carbonates: calcite, dolomite, rhodo- are hosted by metamorphic sequences of Upper Precambrian chrosite, kutnohorite, witherite, aragonite, magnesite, sid- (South Carpathians) and Lower Cambrian ages (East Car- erite, ankerite, Fe-rhodochrosite, smithsonite, azurite, mala- pathians) and their mineralogical composition is quite differ- chite; Borates: tusionite. VI. Sulfates: barite, khademite, ent, although the major minerals are the same, i.e. the oli- jarosite, rozenite, szomolnokite, gypsum, etc.; Wolframates: vines, rhodochrosite, pyroxmangite, rhodonite, etc: (1) Ra- hübnerite, ferberite; VII. Phosphates: hydroxylapatite, car- zoare Mn-Fe deposit (Preluca Mts, East Carpathians), sili- bonate-hydroxylapatite, Mn-apatite, chlorapatite, fluorapa- cate-carbonate-oxide-suphide (2) Dadu, Colacu, Oita, Tolo- tite, switzerite, brushite, monazite-(Ce), monazite-(La), evan- vanu, Puiu, Caprarie, Arsita, Argestru, Todireni, Sarisor, site, xenotime-(Y) (with Eu and Gd), variscite, etc.; Arsen- Dealu Rusului, Mandrileni, Ulm-Sihastria, Holdita, Brosteni, ates: magnussonite, sarkinite, johnbaumite, manganarsite, Borca Mn deposits (Bistrita Mts, East Carpathians), carbon- hedyphane, etc. Vanadates: Ba-vanadates. VIII. Silicates: ate-silicate-oxide-sulphide; (3) Pravat, Leucus, Bretan, A. Nesosilicates : 1.Olivine group: Mn-fayalite, Fe-tephroite, Strambu, Jigureasa, Valea Untului, Cugir Valley, Rovina, tephroite, Mg-tephroite; 2. Manganese humites: sonolite, Rascoala Mn-Fe deposits (Sebes Mts., South Carpathians), alleghanyite, manganhumite; 3. Leucophoenicite humites silicate-carbonate (subsaturated, queluzite) and silicate- group: ribbeite, leucophoenicite, jerrygibbsite; 4. Garnets: quartz (saturated, gondite); (4) Paltinis, Sadu Valley, Sadurel spessartine, spessartine-calderite, grossular, Ti-spessartine- Valley Mn deposits (Cibin Mts, South Carpathians), spessar- grossular, almandine, Mn-almandine, spessartine-andradite- tine type (gondite); (5) Delinesti Mn-Fe deposit (Semenic grossular, anisotropic spessartine-andradite, etc. 5. Zircon, Mts, South Carpathians), silicate-carbonate-oxide. About 350 thorite, titanite, greenovite, etc. B. Sorosilicates: 1. Yoshi- mineral species and mineral varieties have been identified in muraite, bafertisite, etc.; 2. Epidote-zoisite group: epidote, the mentioned deposits. By far the Bistrita occurrences are piemontite, allanite, Mn-allanite, zoisite, “thulite”, androsite- the richest in minerals, including rarities such as silicates- (La), etc. C. Cyclosilicates: 1. Tourmaline group: dravite, arsenates (schallerite, nelenite, etc.), Cl-bearing phyllosili- schorl, etc. D. Inosilicates: 1. Pyroxenes: Mn-ferrosilite, cates (manganpyrosmalite, friedelite, mcgillite, etc.), nambu- Mn-hedenbergite, johannsenite, Fe-johannsenite, augite, lite, bannisterite, androsite-(La), etc. not found yet in South diopside-augite, Na-augite, aegirine-augite, Ti-aegirine- Carpathian occurrences. In addition, the Bistrita minerals augite, aegirine, namansilite, etc.; 2. Pyroxenoids: pyrox- commonly show compositional zoning, which was used to mangite, rhodonite, nambulite, natronambulite, inesite, py- reconstruct the metamorphic evolution. roxferroite (?); Amphiboles: grunerite, manganogrunerite, The minerals from Romanian Carpathian metamorphosed manganocummingtonite, kozulite, magnesioriebeckite, mag- Mn-Fe ores belong to the following mineral classes: I. Na- nesiocummingtonite, “crocidolite”, riebeckite, winchite, tive elements: gold , bismuth, graphite; II. Sulphides: ala- ferroferriwinchite, ferro-anthophyllite, Li-eckermannite, bandite, hauerite (?), pyrite, chalcopyrite, galena, pyrrhotite, richterite, K-richterite, magnesiohornblende, arfvedsonite, cattierite, bornite, löllingite, tetrahedrite, tennantite, ferroglaucophane, “crossite”, Mn-actinolite, ferroactinolite, matildite, bournonite, semseyite, freibergite, boulangerite, Mn-tremolite, etc. E. Phyllosilicates: phlogopite, Mn- molybdenite, Bi arsenide with Cl, sulphide-arsenide with Cl, phlogopite with Ni, norrishite, biotite, Ti-biotite, Mn-biotite, Bi-telluride, tetradymite, skutterudite, matildite, nickeline, muscovite, kinoshitalite, anandite, illite, annite, chloritoid, cobaltite, linneite, kësterite, arsenopyrite, safflorite, geerite, bannisterite, Ba-bannisterite, ganophyllite, parsettensite, breithauptite, stannite, wurtzite, carrollite, glaucodot, ram- manganpyrosmalite, friedelite, caryopilite, schallerite, su- melsbergite, etc. III. Oxides: primary oxides: jacobsite, gilite, nelenite, minnesotaite, ottrélite, pennantite, clino- magnetite, bixbyite, braunite, neltnerite, hausmannite, pyro- chlore, greenalite, antigorite, kellyite, nimite, lennilenapeite, phanite, iwakiite, hematite, ilmenite, senaite (with Sr, Ca, V, coombsite, bementite, sepiolite, etc. F. Tectosilicates: 1. Nb and Zn), cassiterite, thorianite, högbomite, rutile, perov- Feldspar group: albite, microcline, celsian, hyalophane, or- skite, samarskite; quartz group: α-quartz, stishovite (?), coe- thoclase. 2. Helvite group: helvite, genthelvite, homilite. site (?), opal, moganite, etc. and secondary oxides: nsutite, For all the occurrences the metamorphic evolution is pyrolusite, ramsdellite, manganite, hollandite, lithiophorite, quite complex, generally showing several metamorphic manjiroite, goethite, ranciéite, todorokite, birnessite, coro- events, mainly of retrograde character. nadite, crednerite, cryptomelane, pyrochroite, asbolane, dias-