Sedimentary Or Metamorphic Derived

Quartz (specifically Milky Quartz/Quartzite)

Silicon Dioxide (SiO2)

Schist

Mica Schist

Schist

Mica Schist

Schist

Mica Schist

Desert rose

Gypsum (selenite) rosette, CaSO₄·2H₂O

Weathered sandstone or iron-stained quartzite

Quartz-rich sandstone; possibly weakly metamorphosed quartzite (SiO₂ with iron-oxide coatings)

Feldspar (Orthoclase)

Potassium Feldspar (KAlSi3O8)

Hypersthene

Hypersthene (Magnesium Iron Silicate - (Mg,Fe)SiO3)

Likely serpentine-rich ultramafic rock

Serpentinite; chiefly serpentine-group minerals (Mg3Si2O5(OH)4), commonly with magnetite and relict olivine/pyroxene

Serpentine-rich ultramafic rock (likely serpentinite)

Serpentinite; chiefly serpentine-group minerals (Mg₃Si₂O₅(OH)₄), with possible magnetite, carbonates, and relict olivine/pyroxene

Tumbled gray-green metamorphic rock, likely serpentinite or chlorite schist

Serpentinite/chlorite-rich ultramafic metamorphic rock; commonly dominated by antigorite, lizardite, or chlorite with minor magnetite and talc

Dark gray slate (possibly argillite or shale)

Slate, a low-grade metamorphic rock derived mainly from shale; composition commonly quartz, illite/muscovite, chlorite, and clay minerals

Mica Schist

Mica Schist (KAl2(AlSi3O10)(OH)2 / K(Mg,Fe)3(AlSi3O10)(OH)2)

Serpentine

Serpentine group ((Mg,Fe,Ni,Al,Zn,Mn)3(Si,Fe)2O5(OH)4)

Unakite

Unakite (Epidotized Granite)

Yellow-green serpentine (likely)

Serpentine-group phyllosilicate, commonly lizardite or antigorite; approximate formula Mg₃Si₂O₅(OH)₄

Tumbled quartz-rich stone, possibly blue quartz or granite

Quartz (SiO₂), with probable feldspar and dark accessory minerals

Green Aventurine

Aventurine Quartz (SiO2 with Fuchsite inclusions)

Schist

Mica Schist

Zoisite with Ruby (Anyolite)

Anyolite (Calcium aluminium silicate hydroxide with Corundum)

Ruby in Zoisite

Anyolite (composite of Corundum [Al2O3] and Zoisite [Ca2Al3(SiO4)(Si2O7)O(OH)])

Schist

Mica Schist

Schist

Mica Schist

Schist

Mica Schist

Schist

Mica Schist

Green Aventurine

Silicon dioxide (SiO2) with Fuchsite inclusions

Schist

Mica Schist

Green Aventurine

Silicon Dioxide (SiO2) with Chromium-rich Fuchsite mica inclusions

Blue Apatite

Fluorapatite (Ca5(PO4)3F)

Yellow Chalcedony

Silicon Dioxide (SiO2)

Jasper

Silicon dioxide (SiO2)

Schist

Crystalline Schist (often containing Muscovite, Biotte, or Quartz)

Green Opal

Hydrated Silica (SiO2·nH2O)

Rhodonite

Manganese silicate (Mn,Fe,Mg,Ca)SiO3

Yellow Chalcedony (likely carnelian or yellow agate)

Silicon Dioxide (SiO₂)

Jasper with Iron Staining

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Mixed mineral and rock collection, including likely amethyst and assorted tumbled stones

Unidentified mixed specimens; visible purple quartz is likely amethyst (SiO₂)

Rounded river cobbles, likely quartzite and weathered granite

Quartzite (SiO₂) with possible granitic and sandstone companions

Marble

Recrystallized Calcite (CaCO3)

Pink Marble or Rose Quartz (Likely Pink Marble based on carving texture)

Recrystallized Calcite (CaCO3)

Amethyst and Hematite Bracelet

Amethyst (SiO2) and Hematite (Fe2O3)

Unakite

Altered Granite (Epidotized Granite)