macla nº16. junio ‘12 182 revista de la sociedad española de mineralogía

ondestructive Analytical Methodologies for the Mineralogical Characteriation of Mine Materials / NAIARA GOIENAGA-ELIAS (*), JOSE-ANTONIO CARRERO-HERNÁNDEZ, MAITANE OLIVARES-ZABALANDIKOETXEA, LUIS-ÁNGEL FERNÁNDEZ-CUADRADO, JUAN-MANUEL MADARIAGA-MOTA

DTepartment of Analytical Chemistry. University of the Basque Country. P.O. Box 644, 48080 Bilbao (Spain)

INTRODUCTION hardness etc. often in comination nia aman confocal microscope y with detailed nowledge of the regional enishaw enishaw loucester Determination of the actual chemical geological history a first identification shire UK euipped with ecitation composition and crystalline structure of of many rocforming minerals is lasers of nm 1 nm and 2 a mineral is difficult without the proper possile. nm. analytical euipment Dyar and unter A portale nnoamTM aman 200. Whilst most of the traditional t ecomes more difficult to identify the spectrometer BWTEKC. ewar analytical methodologies are useful in more rare minerals mostly present in EEUU provided with a nm estalishing the identification of only minor amounts and often as small ecitation laser. relatively common minerals including crystals. their chemical composition they are not Portable Micro-Energy Dispersive X-Ray very helpful for species which are As an attempt to etter characterie the Fluorescence Spectroscopy (-ED-XRF): comple or when they are polymorphs. mineralogy of the impacted area for the identification of elemental several ind of samples were collected: composition. The portale ArtTa n an outline of the main identification ntec currently Bruer AS Berlin methods developed during the last fifty olling stones outside and inside the ermany was employed in laoratory years in an ongoing effort to mae mines. analysis. minerals show some of their secrets ocs of the galleries walls inside. several hyphenated analytical Soils outside and inside. Handheld Energy Dispersive X-Ray techniues have een developed. Efflorescences newly formed powder Fluorescence Spectrometer (ED-XRF): urthermore in a period in which type reprecipitations inside. for the identification of elemental analysis ased on nondestructive and Particulate matter deposited on composition. A portale analyer direct techniues for their further vegetation in the runoff outside. MET100 Oford nstruments UK application in many fields art allowed in situ elemental analysis. environment etc. are in vogue science Analytical Equipment is asing also not only for in situ Scanning Electron Microscope-Energy measurements ut also for the Raman Spectroscopy: for the molecular Dispersive X-Ray Spectroscopy (SEM- application of a green chemical characteriation. EDS): for elemental characteriation approaches i.e. without the use of and sample imaging. An EO0 chemicals or minimiing their volume. An interesting nondestructive Scanning Electron Microscope Carl Therefore the present wor ets on complementary alternative to the ay eiss TS mH ermany provides the nondestructive techniues such as diffraction is the aman microscopy. electron image acuisitions. An Ma aman Spectroscopy S Scanning Etensive and growing dataases of Energy Dispersive ay Spectrometer Electron MicroscopeEnergy Dispersive reference spectra give S the potential Oford nstruments Aingdon ay Spectroscopy SEMEDS and the to ecome a widely used tool for routine Ofordshire UK is connected to the Energy Dispersive ay luorescence mineral identification asharova SEM to perform the determination of ED for the mineralogical 200. Despite its potential advantages the elemental composition. characteriation of minepolluted areas. e.g. little or no sample preparation multimicronscale single grain analysis RESULTS AND DISCUSSION MATERIALS AND METHODS molecular analysis insitu analysis it has not yet een widely employed y We have studied a numer of spectra of The results here eplained were the geosciences community Hope . A. various minerals Tale 1 summaries otained in 2 aandoned mining areas: et al. 2001. some all with crystals not larger than a a nP mine located in Western Biscay few millimeters. This will demonstrate north of Spain and a Cue mine A portale dispersive aman the strength of the S techniue as it placed at Easterner Biscay. microproe enishaw A100 shows that each spectrum is uniue and

spectrometer enishaw loucester can e used as a sort of fingerprint for The identification of minerals generally shire UK with a nm ecitation the identification of the mineral when a starts in the field y visual eamination. diode. large enough dataase of mineral Based on properties such as colour spectra is availale.

palabras clave: Espectroscopia aman Muestras key words: aman Spectroscopy Environmental samples on medioamientales o destructivo Anlisis in situ. destructive n situ analysis. resumen SEM/SEA 2012 corresponding author: naiara.goyenagaehu.es

macla nº16. junio ‘12 revista de la sociedad española de mineralogía 183

ELEMENT MINERALS it has also een suitale for single crystals as small as a few hundred Lead Litharge, massicot, plattnerite, minium, galena, cerussite, anglesite micrometers. Zincite, sphalerite, rosasite, smithsonite, leiteite, hemimorphite Iron Hematite, goethite, lepidochrocite, pyrite, siderite, sarcopside At the molecular level the information provided for the aove mentioned Tenorite, villamaninite, delafossite, , , olivenite techniues seemed to e also helpful Table 1. Some minerals identified by means of RS. not only for the identification of the presence of impurities ut also for a As shown in ig. 1 some spectra information. or instance the particle semiuantitative analysis of the otained can e found to e a miture sie given y SEM ig. provides environmental samples studied. Since i.e. two or more minerals present in etter nowledge of the health ris occasionally etter results are needed the same spot which is not a prolem assessment associated to the the sample collection may e reuired for S which can gather spectra on aandoned mine studied as far as the for their la analysis i.e. y ED individual grains. atmospheric particulate matter PM nia aman or A100. The results

elow 10 m is considered to e otained thereof may e clearer and harmful i.e. cancer. urthermore the more detailed. Anyway freuently the elemental composition of such PM field measurements are good enough mainly derived from the erosion of the for a good characteriation of the tailing wastes do also inform aout the minerals present in environmental possile riss associated to the metals samples. present i.e. P n S in each type of particle sie. Even if these analytical tools are suitale for the research lined to the geological field the est identification fig 1. A mineral mixture identified by RS. of any mineral however will e that in which converge the results of all the Once having assigned the S to a availale techniues D S concrete mineral its elemental EDS etc. composition may e analyed more in depth. or instance the molecular ACKNOWLEDGEMENTS formula of the minerals itself do also give a clue of the oidation state of the This wor has een financially elements that constitutes it. t is fig 3. A SEM image of a re-precipitated sample after supported y the Basue overnment worldwide now that the redo state of run-off phenomena. through the Berrilur project ef. the elements is directly lined to oth E0022. . oienaga acnowledges the environmental and the human Since a huge amount of minerals may her predoctoral fellowship from the health ris of such components. Thus present impurities an advanced UP/EHU. Technical and human the ris associated can e deduced and elemental analysis of the samples is support provided y the amanLASPEA conseuently the needed control reuired. To achieve this goal several Laoratory of the Ser UP/EHU actions taen. analytical techniues such as ED MC /E ED and ES is also ED or EDS may e applied. or gratefully acnowledged. With regard to the mineral structure the instance ig. shows the elemental possiilities are different. n some composition of a solid sample studied REFERENCES cases as seen in ig. 2 the camera of y EDS. the S microscope at 0 or 100 can Dyar D & Gunter M. (2009): Mineralogy and give a good image of the studied grains. Optical Mineralogy. Mineralogical Society of America, 708 p. Gasharova, B. (2008): Raman, conventional infrared and synchrotron infrared spectroscopy in Mineralogy and Geochemistry: basics and applications. in: ”Instrumental Techniques Applied to Mineralogy and Geochemistry” I. Subias & B. Bauluz, eds. Seminarios SEM, 5, 57-81 fig 4. An EDS spectrum with the identification of several elements present in a efflorescence Hope G.A., Woods, R., Munce, C.G. (2001): sample. Raman microprobe mineral identification. Min. Eng., 14, DOI: 1565-1577. fig 2. Prismatic structures of a sieved (250 m) soil sample seen in a RS camera. CONCLUSIONS 10.1016/S0892-6875(01)00175-3, Goienaga N., Arrieta N., Carrero J.A., Olivares

or a more in depth tetural analysis M., Sarmiento A., Martinez-Arkarazo I., This wor eplains the application of Fernndez L.A., Madariaga J.M. (2011): however SEM turns to e a more nondestructive in situ techniues for Micro-Raman spectroscopic identification suitale tool due to the fact that the the identification of minerals. n the of natural mineral phases and their magnifications are higher. At this point present research S has een weathering products inside an abandoned further study of the results otained successfully used for the identification zinc/lead mine. Spectrochim. Act. A, 80, may provide other ind of helpful of minerals oienaga et al. 2011 and 66-74. DOI: 10.1016/j.saa.2011.01.032.