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Contents : THE AMERICAN MINERALOGIST VOL 52 MAY-JUNE 1967 NEW OCCURRENCE AND DATA OF NOLANITE Cuenlrs M. Tevron Materi'als Analysis Company Palo Allo CaliJornia AND Anrnun S. Rloxr Suraey Menlo Park Lr. S. Geological Calif ornia. Arsrn.qcr Nolanite a vanadium iron oxide occurs in metamorphosed and altered greenstones closely associated with native gold and numerous telluricles in the Kalgoorlie mining disstrict Western Australia. Typically it occurs in euhedral tabular prismatic crystals along or near fractures filled with native gold and coloradoite. Chemical analysis done with the electron microprobe gave: V 3452 Fe 24.32 Ti' 1 . 7 0 A l 0 . 6 1 2 n 0 . 3 3 S i 0 . 1 9 S n 0 . 0 9 O 3 8 . 2 4 w i t h o x y g e n b 1 ' d i f i e r e n c e a v e r a g e weight percent from 17 grains. Iron is present as Fe3+ and vanadium as Va+ and V5+ with VzOs/VzOr:1.57. Nolanite is hexagonal o:5.846 it c:9 254 A ce11volume 273.8 A3 cell contents q7V5 orOu oo calculated density 4.60 g cm-3' Average reFea.arZnc.orSno Alo rsio e5Ti6 measured specific gravity is 4.69 hardness 5 5 and in reflected light nolanite shows strong and distinct bireflectance and anisotropism. INrnooucrrox of gold oresfrom Electron microprobeexaminationof polishedsections of nolanthe Kalgoorlie district Western Australia showedthe presence with the ore minerals. ite a vanadium iron oxide mineral associated Although nolanite was identified in ore samplesfrom many mines in the from the Kalgoorliedistrict the mineral was most abundant in specimens in Middle Lode 865-footlevel South Kalgoorlie mine. AII data presented location. this paper pertain to material from this specific Recognition of nolanite at Kalgoorlie marks the secondrepolted ocwith uranium currenceof the mineral. Prior to this nolanite associated minerals had been identified and described from several mines of the Goldfieldsor Beaverlodgeregion Saskatchewan(Barnes and Qurashi 1952 Robinsonel a 1957). Hanson (1958)studied the crystal structure of nolanite using the chemical analysesof Robinson et al (1957) and assuming 16 oxygen atoms per unit cell. Due to the relatively large grain size of nolanite and the lack of magnetic phasesintergrown with it in the material from Kalgoorlie it was possibleto make clean mineral separations.Based on quantitative chemical analysesmade with the electron microprobe analyzer supported by X-ray diffraction data and measured density the chemical composition is redefined and certain changesin unit-cell contents are suggested. tJ+ NOLANITE /J5 OccunnpNcn eNp AssocrerroNs Nolanite at Kalgoorlie is closely associatedwith massive native gold and numerous telluride minerals in highly altered and metamorphosed greenstones.No sulfide minerals were recognized in samples containing nolanite. Minerals identified from the 865-foot level South Kalgoorlie mine include pyrite chalcopyrite sphalerite tennantite-tetrahedrite altaite coloradoite calaverite krennerite petzite sylvanite native gold calcite dolomite and quartz. Chemical analysesdetermined from electron microprobe spectral scans show native gold to be 93 percent Au and 7 percent Ag by weight. Com- Frc. 1. Small subhedral nolanite grains (NOL) in wallrock along margin of fracture filled with native gold (AU). Gangue at top is massive qaaftz (QTZ). Gangue at bottom with nolanite is quartz (QTZ) chlorite (CHL) and calcite (CC). 275X. positions of telluride minerals calaverite krennerite petzite coloradoite altaite and sylvanite correspond closely to those reported for Kalgoorlie mineralsby Palache Berman and Frondel (1958). Quantitative data on all telluride minerals including several with gold to tellurium ratios unreported to date are included in a manuscript in preparation by Radtke and Taylor. Nolanite is confined to and localized in the greenstonealong the margins of small fractures (Figs. 1 and 2). In some areas fragments of shattered greenstone containing nolanite grains are isolated in the fissures (Fig. 3). Nolanite formed early in the paragenesis before the late fracturing and subsequent massive flood of precious metal mineralization (Fig. 4). Textural evidenceand the generallack of native gold and telluride inclusionsin nolanite indicate that nolanite formed before the ore minerals. Polished section examination shows nolanite to be present in sufficient /JO CHARLES M. TAYI OR AND ARTHUR S. RADTKE Ftc. 2. Large euhedral nolanite grains (NOL) in wallrock along margin of shear zone' Note fracture and breakage of nolanite grains protruding into zone of shearing. Dark gangue is mixture of quartz (QTZ) chlorite (CHL) and calcite (CC). Late coloradoite (COL) and native gold (AU) cement broken nolanite and rvallrock. 275X. amounts to be an ore mineral of vanadium at least locally. The abundance of vanadium in local areas warrants a mineralogical study on a regional basisto determinethe extent of this stageof ore mineralization. PRoPERTTES Pnvsrcal AND OPTTCAL Physical and optical properties of nolanite from Kalgoorlie correspond closelyto those reported by Robinsonet al (1957)for nolanite from Beaverlodge Saskatchewan. The mineral occurs in subhedral to euhedral Frc. 3. Photomicrograph showing fragment of broken wallrock containing nolanite (NOL) caught in shear zone. Fractured nolanite grains are cemented by minor amounts of coloradoite (COL) with late native gold (AU) surrounding broken fragments. 275 X . NOLANITE lJl tabular prismatic grains from 10 to 50 microns in width and up to several hundred microns in length. It is opaque brownish black in powder and submetallic in luster. In polished section under reflectedlight nolanite is strongly bireflectant with colors from medium brown to blue gray in sectionsparallel to the caxis. Sectionsperpendicular to the c-axisshow no bireflectanceand have a uniform medium-brown color. Under crossednichols in sections containing the o and c-axis it is strongly anisotropic with polarization colors from deep red to midnight blue. Frc. 4. Photomicrograph showing strongly shattered greenstone containing grains ol nolanite (NOL). Many nolanite grains broken out from the greenstoneare surrounded and outlined by coloradoite (COL). Note late veinlet of native gotd (AU) at right side with native gold cementing fractured greenstone.275X. Nolanite has a Mohs hardnessof 5 to 5f polished easily and showsuneven fracture. Three determinations of specific gravity gave values of 4.7O 4.67 and 4.70 for an averageol 4.69. Under high-energyelectron No bombardment (30 KV) nolanite shows no cathode luminescence. microchemicaltests were made due to the small grain size and the close association with the more reactive native eold and various tellurides. X-Rav D lrl X-ray powder diffraction data for nolanite from Kalgoorlie are given in Table 1. The X-ray data for nolanite from Beaverlodge Saskatchewan reported by Robinson et at' (1957) is included in Table 1 for comparison. a:5.846 A and Unit-cell constantsdeterminedin the present study are'. ( 1 9 5 7 ) r e p o r t e do : 5 . 8 5 4 A c : 9 . 2 5 4 A w i t h c / a : 1 . 5 8 3 . R o b i n s o ne t a l Saskatchewan' and.c:9.295 A for nolanite from Beaverlodge 738 CHARLES Tlnla M. TAYLOR AND AIITIIUR S. RADTKE Dera ron Nora.Nrre 1. X-Rev Pownnn Drl.lnacrtox lnou Karcoonuo Austner re Observed Nolanite South Kalgoorlie Mine Kalgoorlie Western Australia2 dnt Calculatedr Observed Nolanite Fish Hook Bay Beaverlodge SaskatchewanB dn*t hht @hkl 100 002 101 lo2 110 103 200 tt2 201 004 202 104 203 210 2tl 5. 0 6 463 4.M 3.42 ) o' 2.63 2.53 1L7 5. 0 5 4.62 4.M 3.4r 2.92 2.63 2.53 1 Aa 20 60 t-) tt+ 212 105 204 300 301 2t3 302 006 205 303 106 2r4 220 310 2.M 2.31 2.22 2.lo r.957 1. 9 1 3 r.874 1.814 t.768 1.738 1.708 1 688 1 .660 .626 1.585 1.542 t.494 1.480 1.475 r.474 t.46r 1.404 2.M 2.22 t. vJ.) 85 35 100 40 100 80 60 65 5. 0 9 466 +.47 3.M 2.95 2.66 2. 5 5 2.49 2.+6 2.33 2.23 2.12 1.969 16 55 8 100 t6 90 16 90 40 6 50 1 30 t.812 1.769 1.738 1.710 1 .659 r.628 1.587 1.541 t.494 40 20 40 5 60 +.) t.7i9 1.750 r.719 r.636 1.59s I . J4+J o 6 20 25 13 A 60 1 .495 60 1.463 85 1.461 22B I fndices from least-squares refinement of X-ray powder data using digital computer program (Evans e/ al 1963). 2 Mountof nolanite grains 1 to 10 chemical analysis Table 2. Specimen OD24907 Ore Deposits Collection Stanford University Film 311 1964 Cu/Ni radiation CuKo : 1 . 5 4 1 8 A c u - e . u d i a m e t e r 1 1 4 . 6m m . 3 Film 5865 F. A. Hildebrand U. S. Geological Survey CrKo radiation:2.2909 it 714.7mm diameter camera (Robinson el aI 1957).

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