Rhodochrosite
Manganese Carbonate (MnCO3)
Category
Browse mineral (tectosilicate) specimens identified by the Rock Identifier community.
Rhodochrosite
Manganese Carbonate (MnCO3)
Limonite (Iron Ore)
Limonite (FeO(OH)·nH2O)
Sandstone with Magnetite and Iron Staining
Clastic Sedimentary Rock (contains Fe3O4 and Limonite/Hematite)
Gneiss
Gneiss
Granite Pebbles
Granite (composed primarily of Quartz SiO2, Feldspar (KAlSi3O8 – NaAlSi3O8 – CaAl2Si2O8), and Mica)
Nickel coin (U.S. currency)
Cupronickel (75% Copper, 25% Nickel alloy)
Limonite/Goethite Nodule
Iron Oxyhydroxide (primarily FeO(OH)·nH2O)
Green Fluorite (likely synthetic or heat-treated for jewelry)
Calcium Fluoride (CaF2)
Epidote in Matrix
Epidote; Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH)
Arsenopyrite in Quartz Matrix
Arsenopyrite (FeAsS) with Quartz (SiO2)
Diorite
Phaneritic Intermediate Igneous Rock
Granite
Granite (Felsic Plutonic Rock)
Vesuvianite (Idocrase)
Ca19(Al, Mg, Fe)13(SiO4)10(Si2O7)4(OH, F, O)10
Bornite
Bornite (Cu5FeS4)
Epidote with quartz/feldspar
Epidote, Ca2(Al,Fe)3(SiO4)3(OH)
Fluorite
Calcium Fluoride (CaF2)
Blue Apatite
Fluorapatite (Ca5(PO4)3F)
Fluorite
Fluorite (Calcium Fluoride - CaF2)
Rainbow Fluorite
Calcium Fluoride (CaF2)
Fluorite
Calcium Fluoride (CaF2)
Fluorite
Fluorite (Calcium Fluoride, CaF2)
Amygdaloidal Basalt with Secondary Minerals
Basalt containing secondary mineralization (likely Chlorite, Celadonite, or Zeolites)
Greenstone
Protolith: Basaltic rock
Greenstone
Greenschist / Meta-basalt
Limonite (Iron Ore)
FeO(OH)·nH2O
Black Sand (Magnetite Sand)
Magnetite (Fe3O4)
Gossan (with Limonite/Hematite coating)
Ferruginous Gossan (Fe2O3·nH2O / Fe2O3)
Amygdaloidal Basalt
Amygdaloidal Basalt (with secondary mineral infilling)
Sandstone
Arenite (SiO2 + various cementing minerals)
Bauxite
Bauxite (Al(OH)3 mixed with Fe2O3 and clay minerals)
Turquoise
CuAl6(PO4)4(OH)8·4H2O (Hydrous phosphate of copper and aluminum)
Malachite
Copper carbonate hydroxide [Cu2CO3(OH)2]
Snowflake Obsidian
Obsidian with Cristobalite inclusions
Granite
Granite (Felsic Intrusive Igneous Rock)
Iron-stained Quartz
Silicon Dioxide (SiO2) with Iron Oxide (Limonite/Goethite) inclusions
Granite
Phaneritic plutonic rock (Quartz, Alkali Feldspar, and Plagioclase)
Limonite (often after Pyrite)
Limonite (FeO(OH)·nH2O)
Limonite (Iron Ore)
Limonite (FeO(OH)·nH2O)
Blue Apatite
Fluorapatite (Ca5(PO4)3F)
Note regarding baguette production (not a rock)
Digital text image - Somali language
Granodiorite
Granodiorite (Intermediate intrusive igneous rock)
Sandstone (Ferruginous)
Arenite (Fe2O3 staining)