Potassium Feldspar (Orthoclase / Microcline)
KAlSi3O8 (Potassium Aluminum Silicate)
mineral
Category
Mineral Composite
Browse mineral composite specimens identified by the Rock Identifier community.
Learn about Mineral Composite in the encyclopedia
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Seashell (Calcium Carbonate)
Calcium Carbonate (CaCO3)
mineral
Sandstone
Sedimentary Rock (Quartz Sandstone)
sedimentary
Fossilized bone fragment, possibly vertebra
Fossil bone (mineralized hydroxyapatite; exact taxon indeterminate)
fossil
Picture Jasper
Silicon Dioxide (SiO2) with iron oxide and silicate minerals
sedimentary
Green Fluorite
Calcium Fluoride (CaF2)
mineral
Marble
Metamorphic rock composed of Recrystallized Carbonate Minerals (chiefly CaCO3)
metamorphic
Tumbled quartz or calcite specimen
Quartz (SiO₂) or calcite (CaCO₃); exact identification requires testing
mineral
Greenstone / Metabasalt
Chlorite schist or Epidiorite
metamorphic
Greenstone
Protolith: Basaltic rock
metamorphic
Greenstone
Greenschist / Meta-basalt
metamorphic
Likely quartz-rich mineral specimen
Quartz (SiO₂), possibly milky quartz or quartz-bearing rock
mineral
Weathered serpentinized ultramafic rock
Serpentinite; chiefly serpentine-group minerals, commonly with magnetite, brucite, talc, and relict olivine/pyroxene
metamorphic
Green Fluorite
Calcium fluoride (CaF2)
mineral
Quartz (Druzy)
Silicon Dioxide (SiO2)
mineral
Fluorite with Quartz coating
Calcium Fluoride (CaF2) with Silicon Dioxide (SiO2)
mineral
Fluorite
Calcium fluoride, CaF2
Mineral
Mixed Mineral Collection (Quartz, Amethyst, Rose Quartz, Pyrite, etc.)
Mixed Silicates and Sulfides (SiO2, FeS2)
mineral
Sandstone (Tumbled/River Pebble)
Arenite (composed primarily of SiO2)
sedimentary
Tumbled greenstone (likely serpentine or nephrite-like material)
Serpentinite, chiefly serpentine-group minerals; exact identification requires testing
metamorphic
Likely a small rough mineral specimen
Unidentifiable from the image; possibly a mica-bearing rock or green mineral
mineral
Peridotite (Dunite)
Olivine-rich Peridotite ((Mg,Fe)2SiO4)
igneous
Diamond
Carbon (C)
gemstone
Sandstone Pebble
Quartzose Sandstone (Sedimentary Rock)
sedimentary
Quartz-bearing pegmatite
Quartz (SiO₂) with feldspar and mica, likely a granitic pegmatite
igneous
Tumbled green stone, likely serpentine
Serpentine-group minerals, commonly antigorite or lizardite; approximate formula Mg₃Si₂O₅(OH)₄
mineral
Likely lepidolite-bearing mica or purple fluorite
Lepidolite: K(Li,Al)3(Si,Al)4O10(F,OH)2; alternatively fluorite: CaF2
mineral
Vesuvianite (Idocrase)
Ca19(Al, Mg, Fe)13(SiO4)10(Si2O7)4(OH, F, O)10
mineral
Bornite
Bornite (Cu5FeS4)
mineral
Epidote with quartz/feldspar
Epidote, Ca2(Al,Fe)3(SiO4)3(OH)
metamorphic
Polished granite slab
Granite, a coarse-grained quartz–feldspar plutonic rock
igneous
Fossilized tooth, likely mammoth or mastodon molar fragment
Proboscidean molar enamel and dentin; Mammuthus or Mammut sp. (tentative)
fossil
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)
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