Fossilized tooth, likely mammoth or mastodon molar fragment
Proboscidean molar enamel and dentin; Mammuthus or Mammut sp. (tentative)
fossil
Category
Mineral
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Gneiss with Quartz Veining
Gneiss (High-grade metamorphic rock)
metamorphic
Gneiss
Gneiss
metamorphic
Granite Gneiss
Gneiss (Derived from Granite protolith)
metamorphic
Granite Pebbles
Granite (composed primarily of Quartz SiO2, Feldspar (KAlSi3O8 – NaAlSi3O8 – CaAl2Si2O8), and Mica)
igneous
Nickel coin (U.S. currency)
Cupronickel (75% Copper, 25% Nickel alloy)
man-made alloy (metallic)
Vesicular basalt (likely weathered lava rock)
Basalt; chiefly plagioclase, pyroxene, and often olivine
igneous
Conglomerate (or Breccia / Porphyry)
Clastic Sedimentary Rock (Conglomerate / Sandstone)
sedimentary
Botryoidal blue-green mineral specimen, likely hemimorphite
Hemimorphite, Zn4Si2O7(OH)2·H2O; possibly associated with calcite or smithsonite
mineral
Greenschist (Chlorite Schist)
Greenschist (containing Chlorite, Actinolite, and Epidote)
metamorphic
Fossilized oyster shell
Ostrea/Exogyra sp.; calcium carbonate (mostly calcite)
fossil
Granite Gneiss
Gneiss (high-grade metamorphic rock)
metamorphic
Magnetite (Lodestone variant potential)
Magnetite (Fe3O4)
mineral
Sandstone Pebble
Arenite (SiO2 based)
sedimentary
Prehnite
Prehnite - Ca2Al(AlSi3O10)(OH)2
mineral
Sandstone Pebble
Arenite (SiO2 complex)
sedimentary
Limonite (Iron Ore)
Limonite (FeO(OH)·nH2O)
mineral
Tiger's Eye
Pseudomorph of Quartz after Crocidolite (SiO2)
metamorphic
Satin Spar (Gypsum)
Calcium Sulfate Dihydrate (CaSO4·2H2O)
mineral
Green Fluorite
Calcium Fluoride (CaF2)
mineral
Satin Spar (Gypsum)
Calcium Sulfate Dihydrate (CaSO4·2H2O)
mineral
Fluorite
Calcium fluoride (CaF2)
mineral
Pyrite
Iron Sulfide (FeS2)
mineral
Mixed Gemstone and Mineral Collection
Mixed Silica and Carbonate minerals (SiO2, CaSO4·2H2O, etc.)
mineral
Quartz-rich pegmatite with mica and dark inclusions
Pegmatite; chiefly quartz (SiO₂), with feldspar and biotite/tourmaline inclusions
igneous
Fluorite
Calcium Fluoride (CaF2)
mineral
Quartz-bearing pegmatitic rock, likely granite/pegmatite
Feldspar–quartz pegmatite; chiefly K-feldspar, plagioclase, quartz, and possible mica
igneous
Quartz (Druzy / Crystalline)
Silicon Dioxide (SiO2)
mineral
Fluorite
Calcium Fluoride (CaF2)
mineral
Fluorite
Calcium Fluoride (CaF2)
mineral
Obsidian
Volcanic Glass (SiO2)
igneous
Snowflake Obsidian
Obsidian with Cristobalite inclusions (SiO2)
igneous
Serpentinite
Serpentinite (Mg, Fe, Ni, Al, Zn, Mn)2-3(Si, Al, Fe)2O5(OH)4
metamorphic
Diorite (Porphyritic) / Granite
Plutonic Igneous Rock (Granodiorite / Diorite)
igneous
Granite
Intrusive igneous rock
igneous
Green Fluorite (Botryoidal/Massive)
Calcium Fluoride (CaF2)
mineral
Milky Quartz with Iron Staining
Silicon Dioxide (SiO2) with Limonite/Goethite
mineral
Vanadinite
Pb5(VO4)3Cl
mineral
Polished Hematite Tower
Hematite (Fe2O3)
mineral
Chrysocolla (or Turquoise/Aventurine)
Cu2-xAlx(H2-xSi2O5)(OH)4·nH2O
mineral
Stalagmite (Flowstone)
Speleothem (Calcium Carbonate, CaCO3)
sedimentary
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
mineral