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2017 BMC AUCTION SPECIMENS (2017 Auction Date Is Saturday, 21 January)

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2017 BMC AUCTION SPECIMENS (2017 Auction Date Is Saturday, 21 January) A SAMPLER OF SELECTED 2017 BMC AUCTION SPECIMENS (2017 Auction Date is Saturday, 21 January) Volume 2 Apophyllite [KCa4(Si4O10)2F•8(H2O)], Stilbite [NaCa4Al8Si28O72•30(H2O)] & Scolecite [CaAl2Si3O10•3(H2O)] Locality Pune District (Poonah District) Maharashtra India Size 9.5 x 7.0 x 6.6 cm. BMC Purchase Scolecite Crystal System: Monoclinic Physical Properties Transparency: Transparent - Subtranslucent Photograph by Mike Haritos Mohs hardness: 5 to 5.5 Density: 2.16 to 2.4 gm/cm3 Streak: White Luster: Vitreous - Silky Fluorite [CaF2] & Calcite [CaCO3] Locality Cave-in-Rock Sub- District Illinois - Kentucky Fluorspar District Hardin Co., Illinois Size 12.2 x 7.5 x 5.8 cm BMC Purchase Fluorite Crystal System: Isometric Physical Properties Transparency: Transparent Mohs hardness: 4 Density: 3.18 - 3.56 gm/cm3 Streak: White Photograph by Mike Haritos Luster: Vitreous, Dull Quartz [SiO2] on Pyrite [FeS2] Locality Trepča Stan Terg Mine Trepča complex, Trepča valley District of Kosovska Mitrovica, Kosovo Size 9.4 x 9.0 x 7.4 cm Donated by Mike Haritos MINERAL QUARTZ PYRITE Crystal System Trigonal Isometric Transparent, Transparency Opaque Translucent Hardness 7 6 to 6.5 2.65 to 2.66 Density 4.8 to 5 gm/cm3 gm/cm3 Greenish-black to Streak White Photograph by Mike Haritos Brownish-black Luster Vitreous Metallic Barite [BaSO4] on Fluorite [CaF2] Locality Xiefang Mine Ruijin County Ganzhou Prefecture Jiangxi Province China Size 14.9 x 11.9 x 8.1 cm Donated by Bill Metropolis Barite Crystal System: Orthorhombic Physical Properties Transparency: Transparent, Translucent, Opaque Mohs hardness: 3 to 3.5 Density: approx 4.5 gm/cm3 Photograph by Mike Haritos Streak: White Luster: Vitreous, Pearly Stilbite [NaCa4Al8Si28O72•30(H2O)] on Stalactitic Chalcedony (Quartz) [SiO2] Locality Pune District (Poonah District) Maharashtra India Size 7.0 x 6.1 x 4.1 cm BMC Purchase MINERAL Stilbite Chalcedony Crystal System Monoclinic Triclinic Transparent, Opaque, Transparency Subtransparent, Transparent, Translucent Translucent Hardness 3.5 to 4 6.5 to 7 Density 2.1 – 2.2 gm/cm3 2.6 – 2.65 gm/cm3 Streak White White Photograph by Mike Haritos Luster Vitreous - Pearly Vitreous Quartz [SiO2] var. Amethyst Locality Thunder Bay District Ontario Canada Size 17.4 x 12.9 x 4.1 cm Donated by Bill Metropolis Crystal System: Trigonal Physical Properties Transparency: Transparent, Translucent Mohs hardness: 7 Density: 2.65 to 2.66 gm/cm3 Streak: White Photograph by Mike Haritos Luster: Vitreous Galena [PbS] Locality Krushev dol deposit Krushev dol mine Madan ore field Rhodope Mts Smolyan Oblast Bulgaria Size: 5.6 x 4.5 x 3.5 cm BMC Purchase Galena Crystal System: Isometric Physical Properties Transparency: Opaque Mohs hardness: 2.5 Density: approx 7.58 gm/cm3 Streak: Lead - Grey Photograph by Mike Haritos Luster: Metallic, Dull Powellite [CaMO4] & Stilbite [NaCa4Al8Si28O72•30(H2O)] Locality Pune District (Poonah District) Maharashtra India Size 5.5 x 4.5 x 3.0 cm BMC Purchase MINERAL Powellite Stilbite Tetragonal- Crystal System Monoclininc Dipyramidal Transparent, Transparent, Transparency Subtransparent, Translucent Translucent Hardness 3.5 to 4 3.5 to 4 Photograph by Mike Haritos Density 4.34 gm/cm3 2.1 – 2.2 gm/cm3 Streak Light yellow White Powellite exhibits bright yellow Adamantine - fluorescence under SWUV light Luster Vitreous - Pearly Resinous Sphalerite [ZnS] & Galena [PbS] Locality Krushev dol deposit (Krusov dol deposit) Krushev dol mine Madan ore field Rhodope Mountains Smolyan Oblast Bulgaria Size 8.5 x 5.2 x 2.3 cm Photograph by Mike Haritos BMC Purchase Sphalerite Crystal System: Isometric Sphalerite Physical Properties Transparency: Transparent, Translucent Mohs hardness: 3.5 to 4 Density: 3.9 - 4.1 gm/cm3 Streak: Pale Yellow to Brown Luster: Adamantine, Resinous Pentagonite [Ca(VO)Si4O10·4H2O] Locality Pune District (Poonah District) Maharashtra India Size 4.1 x 3.5 x 3.2 cm BMC Purchase Pentagonite Crystal System: Orthorhombic Physical Properties Transparency: Transparent Mohs hardness: 4 to 5 Density: 2.33 gm/cm3 Streak: Light Blue Photograph by Mike Haritos Luster: Vitreous, Resinous Mesolite [Na2Ca2Al6Si9O30•8(H2O)] and Stilbite [NaCa4Al8Si28O72•30(H2O)] Locality Pune District (Poonah District) Maharashtra India Size 7.0 x 3.2 x 3.2 cm BMC Purchase Mesolite Crystal System: Monoclinic Physical Properties Transparency: Transparent - Translucent Photograph by Mike Haritos Mohs hardness: 5 Density: 2.2 to 2.4 gm/cm3 Streak: White Luster: Vitreous, Silky Fluorite [CaF2] Locality Hunan China Size 15.3 x 10.5 x 8.4 cm. Fluorite Crystal System: Isometric Physical Properties Transparency: Transparent Mohs hardness: 4 Density: 3.18 - 3.56 gm/cm3 Streak: White Photograph by Mike Haritos Luster: Vitreous, Dull Calcite [CaCO3] Locality China Size 6.7 x 5.5 x 4.0 cm BMC Purchase Calcite Crystal System: Trigonal Physical Properties Transparency: Transparent, Translucent Mohs hardness: 3 Density: 2.71 gm/cm3 Streak: White Luster: Vitreous, Sub-Vitreous, Resinous, Photograph by Mike Haritos Waxy, Pearly Ammonite Fossil Locality Alberta Canada. Size 7.5 x 6.2 x 2.3 cm BMC Purchase Photograph by Mike Haritos Calcite [CaCO3] Locality Chang-Lin Mine China Size 6.3 x 4.5 x 4.5 cm BMC Purchase Calcite Crystal System: Trigonal Physical Properties Transparency: Transparent, Translucent Mohs hardness: 3 Density: 2.71 gm/cm3 Streak: White Luster: Vitreous, Sub-Vitreous, Resinous, Waxy, Pearly Photograph by Mike Haritos Dioptase [CuSiO2(OH)2] Locality Guchab Namibia Size 6.0 x 5.5 x 5.3 cm BMC Purchase Crystal System: Trigonal Physical Properties Transparency: Transparent to Translucent Mohs hardness: 5 Density: 3.28 to 3.35 gm/cm3 Streak: Green Luster: Vitreous Photograph by Mike Haritos Smithsonite [Zn(CO3)] Locality Choix Sinola Mexico Size 4.5 x 4.3 x 4.0 cm 120 g Donated by Don Olson Crystal System: Trigonal Physical Properties Transparency: Subtransparent to Translucent Mohs hardness: 4.5 Density: 4.4 to 4.5 gm/cm3 Streak: White Photograph by Mike Haritos Luster: Vitreous 2+ Calcite [CaCO3] & Chalcopyrite [CuFe S2] Locality Sweetwater Mine Reynolds County Missouri Size 4.9 x 4.9 x 3.4 cm 57 g Donated by Don Olson MINERAL CALCITE CHALCOPYRITE Crystal System Tetragonal Tetragonal Transparent, Transparency Opaque Translucent Hardness 3 3.5 4.1 to 4.3 Density 2.71 gm/cm3 gm/cm3 Photograph by Mike Haritos Streak White Greenish black Vitreous, Resinous, Luster Metallic Waxy, Pearly 2+ Rhodochrosite [Mn (CO3)] & Pyrite [FeS2] Locality Wutong Mine Wuzhou Prefecture Guangxi Zhuang Autonomous Republic China Size 5.0 x 3.8 x 2.5 cm 47 g Donated by Collector’s Edge Rhodochrosite Crystal System: Trigonal Physical Properties Transparency: Translucent to Photograph by Mike Haritos Subtranslucent Mohs hardness: 3 Density: 3.69 gm/cm3 Streak: White Luster: Vitreous Tourmaline 2+ 3+ * [(Na,Ca)(Mg,Li,Al,Fe ,Fe )3(Al,Mg)6(BO3)3Si6O18(OH,O,F)4] Locality Minas Gerais Brazil Size 7.2 x 4.0 x 3.1 cm 129 g Donated by Collector’s Edge Crystal System: Trigonal Formula: * The formula is general and includes all options within the tourmaline group Physical Properties Transparency: Transparent to Opaque Mohs hardness: 7 to 7.5 Density: 2.9 to 3.2 gm/cm3 Streak: White Luster: Vitreous Photograph by Mike Haritos Tourmaline 2+ 3+ * [(Na,Ca)(Mg,Li,Al,Fe ,Fe )3(Al,Mg)6(BO3)3Si6O18(OH,O,F)4] Locality Skardu Pakistan Size 4.3 x 1.8 x 1.7 cm 11 g Donated by Barbara Liebman Crystal System: Trigonal Formula: * The formula is general and includes all options within the tourmaline group Physical Properties Transparency: Transparent to Opaque Mohs hardness: 7 to 7.5 Density: 2.9 to 3.2 gm/cm3 Streak: White Luster: Vitreous Photograph by Mike Haritos Pyrite [FeS2] Locality Navajun La Roija Spain Size 6.5 x 6.5 x 5.4 cm 304 g BMC Purchase Pyrite Crystal System: Isometric Physical Properties Transparency: Opaque Mohs hardness: 6 to 6.5 Density: 4.8 to 5 gm/cm3 Streak: Greenish-black to Brownish-black Photograph by Mike Haritos Luster: Metallic Galena [PbS] Locality Krushev dol deposit Krushev dol mine Madan ore field Rhodope Mountains Smolyan Oblast Bulgaria Size: 6.5 x 6.0 x 2.5 cm. BMC Purchase Crystal System: Isometric Physical Properties Transparency: Opaque Mohs hardness: 2.5 Density: approx 7.58 gm/cm3 Streak: Lead - Grey Photograph by Mike Haritos Luster: Metallic, Dull .
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