Mineral Specimen

Epidote

Epidote (Ca2(Al, Fe)3(SiO4)3(OH))

Muscovite Mica

Muscovite (KAl2(AlSi3O10)(OH)2)

Muscovite Mica

KAl2(AlSi3O10)(OH)2

Possible industrial slag or basaltic volcanic glass

Likely iron-rich vitreous slag; natural alternative: basaltic glass (tachylite)

Amethyst cabochon jewelry

Amethyst, purple variety of quartz (SiO₂)

Calcite (likely chalky calcite fragment)

Calcite, calcium carbonate (CaCO₃)

Faceted color-change gemstone, likely synthetic alexandrite or glass imitation

Alexandrite: chrysoberyl, BeAl₂O₄; exact identification requires gemological testing

Tumbled dark sulfide-rich mineral specimen (possibly pyrite/marcasite)

Tentatively iron disulfide, FeS₂; exact identification requires testing

Polished yellow calcite

Calcite (calcium carbonate, CaCO₃)

Uncertain dark metallic mineral specimen, possibly specular hematite or magnetite

Likely hematite (Fe₂O₃) or magnetite (Fe₃O₄); image alone is insufficient for firm identification

Likely polished dark stone or mineral specimen (unidentifiable from image)

Undetermined; possibly dark quartz-rich material, basalt, or obsidian

Quartz-rich hydrothermal mineral specimen, possibly vanadinite-bearing matrix

Quartz (SiO₂) with unidentified red-brown accessory minerals; exact species requires testing

Chrysocolla-bearing copper mineral specimen (probable turquoise/chrysocolla mix)

Chrysocolla, Cu₂H₂Si₂O₅(OH)₄·nH₂O, with possible turquoise CuAl₆(PO₄)₄(OH)₈·4H₂O and copper oxides

Likely brown quartz-rich rock or iron-stained mineral specimen

Indeterminate; possibly iron-stained quartz (SiO₂) with limonite/goethite coatings

Tumbled or naturally etched mica-rich mineral specimen, likely muscovite

Muscovite, KAl₂(AlSi₃O₁₀)(OH)₂; possibly phlogopite mica

Tumbled metallic sulfide mineral specimen, likely pyrite-bearing ore

Likely pyrite (FeS₂) with associated sulfides and host rock; exact identification requires testing

Calcite (Honey Calcite and Agate)

Calcium Carbonate (CaCO3)

Weathered sandstone or granitic rock fragment

Likely quartz-rich sandstone; exact identification requires testing

Chalcopyrite

Copper Iron Sulfide (CuFeS2)

Quartz Mineral

Silicon Dioxide (SiO2)

Chrysocolla with Malachite

Cu2-xAlx(H2-xSi2O5)(OH)4%CnH2O (Chrysocolla)

K-Feldspar (Potassium Feldspar)

Potassium Feldspar (KAlSi3O8)

Mica / Muscovite or Biotite

Phyllosilicate mineral group (e.g., KAl2(AlSi3O10)(OH)2)

Chalcopyrite (Peacock Ore)

Chalcopyrite (CuFeS2)

Mica (Muscovite or Biotite)

Sheet silicate mineral group (e.g., KAl2(AlSi3O10)(F,OH)2)

Feldspar

Aluminosilicate (KAlSi3O8 - NaAlSi3O8 - CaAl2Si2O8)

Quartz Pebble

Silicon Dioxide (SiO2)

Limonite

FeO(OH)·n(H2O)

Copper Ore (Malachite and Limonite bearing)

Cuprite, Malachite, and Limonite mixture

Yellow Quartz

Silicon Dioxide (SiO2)

Microcline Feldspar (Amazonite or White Feldspar)

KAlSi3O8

K-Feldspar (Potassium Feldspar / Pink Feldspar)

KAlSi3O8 (Potassium Aluminum Silicate)

Chalcopyrite

Copper iron sulfide (CuFeS2)

Botryoidal Chalcedony / Quartz

Silicon Dioxide (SiO2)

Epidote

Epidote (Ca2(Al,Fe)3(SiO4)3(OH))

Chrysocolla-rich copper ore

Chrysocolla, a hydrated copper aluminosilicate (approximately (Cu,Al)₂H₂Si₂O₅(OH)₄·nH₂O), possibly mixed with malachite or turquoise-group minerals

Quartz crystal cluster in matrix

Silicon dioxide (SiO2)

Fluorite

Calcium Fluoride (CaF2)

Banded Iron Formation (Fragment)

Banded Iron Formation (BIF)

Pyrite in Quartz Matrix

Iron Sulfide (FeS2) embedded in Silicon Dioxide (SiO2)

Potassium Feldspar (Orthoclase)

Orthoclase (KAlSi3O8)

Quartz on Host Rock

Silicon Dioxide (SiO2)