Sandstone (Ferruginous)
Arenite (with high iron oxide content)
sedimentary
Category
Mineral Precipitate (Anthropogenic Context)
Browse mineral precipitate (anthropogenic context) specimens identified by the Rock Identifier community.
Learn about Mineral Precipitate (Anthropogenic Context) in the encyclopedia
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Fluorite (Rainbow/Purple Fluorite)
Calcium Fluoride (CaF2)
mineral
Iridium sand or Osmium-Iridium nugget
Iridosmine / Osmiridium (Platinoid grouping)
mineral
Milky Quartz with Mineral Inclusions
Quartz (Silicon Dioxide - SiO2)
mineral
Flesh-colored Quartz Mineral
SiO2 (Silicon Dioxide) with Iron Impurities
mineral
Slate
Foliated Metamorphic Rock (primarily composed of quartz, illite, chlorite, and micas)
metamorphic
Granite
Granite
igneous
Limonite Concretion (Ironstone)
Limonite (Hydrated Iron(III) Oxide-Hydroxide, FeO(OH)·nH2O)
sedimentary
Limonite (Iron Ore)
FeO(OH)·nH2O (Hydrated Iron Oxide)
mineral
Limonite (Iron Ore)
FeO(OH)·nH2O (Hydrous ferric oxide)
mineral
Limonite (vibrant yellowish-brown iron oxide)
Limonite (FeO(OH)·nH2O)
mineral
Bauxite
AlOx(OH)3-2x (mixture of Gibbsite, Boehmite, and Diaspore)
sedimentary
Quartz Pebble
Quartz (Silicon Dioxide, SiO2)
mineral
Lapis Lazuli
Lazurite-rich metamorphic rock (approx. (Na,Ca)8(AlSiO4)6(S,Cl,SO4,OH)2)
metamorphic
Moss Agate
Chalcedony (Silicon Dioxide) with Chlorite or Iron/Manganese inclusions (SiO2)
mineral
Granite
Granite
igneous
Milky Quartz with Mineral Inclusions
Silicon Dioxide (SiO2)
mineral
Milky Quartz with Mineral Inclusions
Quartz (Silicon Dioxide, SiO2)
mineral
Silver (Native Silver Mineral)
Ag (Native Silver), Alloyed 90% Ag / 10% Cu
mineral
General Rock and Mineral Collection (Center: Angelite / Blue Anhydrite)
Anhydrite (Calcium Sulfate, CaSO4)
Mineral
Milky Quartz with Mineral Inclusions
Silicon Dioxide (SiO2)
mineral
Pearl (as a biogenic mineral/gemstone)
Calcium Carbonate (mostly Aragonite), CaCO3
mineral
River Cobble (Sandstone)
Arenite (primarily SiO2)
sedimentary
Gold-bearing Quartz
Lode Gold in Silicon Dioxide (SiO2)
mineral
Granodiorite
Granodiorite
Igneous
Ferruginous Quartz
Silicon Dioxide (SiO2) with Iron Oxide (Fe2O3) inclusions
mineral
Selenite
Gypsum (Calcium Sulfate Dihydrate) - CaSO4·2H2O
mineral
Peacock Ore
Bornite (Cu5FeS4) or Chalcopyrite treated with acid
mineral
Spiny Oyster Shell
Spondylus (Calcium Carbonate, CaCO3)
mineral
Limonite/Hematite Ironstone
Goethite-rich Ironstone (FeO(OH) · nH2O)
sedimentary
Brimstone (Native Sulfur)
Native Sulfur (S)
mineral
Malachite
Malachite - Cu2CO3(OH)2
mineral
Sandstone
Arenite (Clastic Sedimentary Rock)
sedimentary
Turquoise
Hydrated phosphate of copper and aluminium (CuAl6(PO4)4(OH)8·4H2O)
mineral
Fuchsite (Chrome Mica)
K(Al,Cr)2(AlSi3O10)(OH)2
mineral
Lepidolite in Quartz (Obelisk)
K(Li,Al)3(Al,Si,Rb)4O10(F,OH)2 (Lepidolite)
metamorphic
Bumblebee Jasper
Fossiliferous Volcanic Rock (composed of Calcium Carbonate, Manganese Oxides, and Arsenic Sulfides)
igneous
Chrysocolla
Hydrated copper phyllosilicate mineral (Cu,Al)2H2Si2O5(OH)4·n(H2O)
mineral
Turquoise in Matrix
Hydrated phosphate of copper and aluminium (CuAl6(PO4)4(OH)8·4H2O)
mineral
Sandstone (with potential mineral inclusions)
Clastic sedimentary rock (primarily Quartz, SiO2)
sedimentary
Red Sandstone
Arenite (Ferruginous Sandstone)
sedimentary
Pink Granite
Phaneritic Plutonic Felsic Igneous Rock (Granite)
igneous