Mineral Specimen

Staurolite (Cross Stone)

Staurolite (Fe2+2Al9Si4O23(OH))

Polished orange calcite point

Calcite (CaCO₃), likely honey/orange calcite

Smoky Quartz

SiO2 (Silicon Dioxide)

Milky quartz with iron-oxide staining

Quartz, silicon dioxide (SiO₂), likely massive or coarsely crystalline; brown areas are limonite/goethite staining

Staurolite

Staurolite (Fe2Al9O6(SiO4)4(O,OH)2)

Quartz-rich metallic sulfide ore (probable pyrite-bearing rock)

Pyrite, FeS₂, in a quartz-rich host; exact identification is uncertain from the image

Mixed Gemstone Bracelet

Mixed natural minerals and rocks (e.g., Rhodonite, Malachite, Sodalite, Rose Quartz, Black Tourmaline, Quartz/Chalcedony variants)

Mica-rich schist, likely lepidolite or muscovite schist

Mica schist; predominantly muscovite KAl₂(AlSi₃O₁₀)(OH)₂, possibly lithium-rich lepidolite

Green tourmaline crystal (likely elbaite)

Elbaite tourmaline, a complex borosilicate: Na(Li,Al)₃Al₆(BO₃)₃Si₆O₁₈(OH)₄

Pyrite with quartz

Pyrite (FeS₂) with quartz (SiO₂), possibly minor chalcopyrite

Wollastonite

Calcium Inosilicate Mineral, CaSiO3

Specular Hematite (Specularite)

Iron Oxide (Fe2O3)

Iron-stained quartz (likely quartzite or quartz-rich rock)

Quartz, silicon dioxide (SiO₂), with iron-oxide staining

Lepidolite Ore

K(Li,Al)3(Al,Si,Rb)4O10(F,OH)2

Amethyst

Amethyst (Silicon Dioxide with iron impurities, SiO2)

Nephrite (a form of Jade)

Nephrite (a variety of the mineral actinolite, Ca2(Mg,Fe)5Si8O22(OH)2)

Milky quartz (likely quartz-rich rock)

Quartz, silicon dioxide (SiO₂)

Azurite in Gossan

Azurite (Cu3(CO3)2(OH)2) in Limonite/Goethite matrix

Pyrite cluster in a sulfide-rich ore matrix

Pyrite, FeS₂, likely with pyrrhotite and/or chalcopyrite in matrix

Citrine Quartz

Crystalline Silicon Dioxide (SiO2) with Ferric Iron impurities

Actinolite

Ca2(Mg,Fe)5Si8O22(OH)2

Kyanite (Green and Blue varieties)

Kyanite (Al2SiO5)

Moonstone (bead form)

Potassium Aluminum Silicate (KAlSi3O8) - a variety of Orthoclase Feldspar

Green Fluorite

Calcium Fluoride (CaF2)

Amethyst

Silicon dioxide (SiO2)

Rhodochrosite

Manganese Carbonate (MnCO3)

Pale green tumbled mineral fragment, likely serpentine or green calcite

Probable serpentine-group mineral (Mg3Si2O5(OH)4) or, less likely, calcite (CaCO3); identification is uncertain from the photograph

Milky quartz (quartz-rich rock fragment)

Quartz, silicon dioxide (SiO₂)

Mica-rich schist

Muscovite–biotite schist, commonly quartz-bearing

Celestite (Celestine)

Strontium sulfate (SrSO4)

Stichtite in Serpentine (Atlantisite)

Mg6Cr2CO3(OH)16·4H2O (Stichtite) / Mg3Si2O5(OH)4 (Serpentine)

Iron-Stained Quartz (Red/Hematoid Quartz)

Silicon Dioxide (SiO2) with Hematite/Goethite inclusions

Quartz–feldspar pegmatite specimen

Granitic pegmatite, chiefly quartz (SiO₂), potassium feldspar (KAlSi₃O₈), and mica-group minerals

Chalcedony (Botryoidal)

Silicon Dioxide (SiO2)

Lazulite

Lazulite (Mg,Fe2+)Al2(PO4)2(OH)2

Aragonite Star Cluster

Aragonite (Calcium Carbonate, CaCO3)

White calcite (likely tumbled calcite or marble fragment)

Calcite, calcium carbonate (CaCO₃); if the specimen is granular and rock-like, it may be marble, a calcite-rich metamorphic rock

Garnet

Almandine/Pyrope Garnet (Silicate Mineral Group)

Ferruginous Quartz (Iron-stained Quartz)

Silicon Dioxide (SiO2) with Hematite/Limonite impurities

Pyrite (Fool's Gold)

Iron Disulfide (FeS2)

Fluorite

Calcium Fluoride (CaF2)

Peacock ore (iridescent chalcopyrite, possibly bornite)

Chalcopyrite, CuFeS₂; the iridescent surface may be natural tarnish or artificial acid treatment. Similar material is bornite, Cu₅FeS₄.