Granite
Granite (composed primarily of Quartz, Potassium Feldspar, Plagioclase, and Biotite/Amphibole)
Category
Browse mineral (extraterrestrial) specimens identified by the Rock Identifier community.
Granite
Granite (composed primarily of Quartz, Potassium Feldspar, Plagioclase, and Biotite/Amphibole)
Gneiss
Gneiss
Gneiss
Gneiss (High-grade Metamorphic Rock)
Gneiss
Gneiss (High-grade metamorphic rock)
Gneiss
Gneiss
Granite Pebble (Weathered)
Phaneritic Felsic Igneous Rock
Banded Gneiss
Gneiss (Metamorphic Rock)
Diorite
Diorite
Quartz Vein / Quartz Matrix
Silicon Dioxide (SiO2)
Raw Corundum (Sapphire/Ruby variant)
Aluminum oxide (Al2O3)
Banded Gneiss
Gneiss (pronounced 'nice')
Sandstone Concretion
Clastic sedimentary rock (primarily Quartz SiO2 with mineral cement)
Blue-green raw mineral specimen, likely apatite
Fluorapatite, Ca₅(PO₄)₃F (probable; visual identification only)
Boxwork Siderite or Sepatarian Nodule Weathering
Siderite (FeCO3) with secondary mineralization or Boxwork Geode fragment
Quartz with Pyrite
Silicon Dioxide (SiO2) with Iron Sulfide (FeS2)
Schist
Mica schist, likely muscovite–biotite schist with quartz and feldspar
Sandstone
Arenite (clastic sedimentary rock)
Limonite (Iron Ore)
Limonite (FeO(OH)·nH2O)
Pyrite (or Arsenopyrite / Ore mineral aggregate)
FeS2 (Iron Sulfide)
Limonite (often after Pyrite)
Limonite (FeO(OH)·nH2O)
Sandstone with Magnetite and Iron Staining
Clastic Sedimentary Rock (contains Fe3O4 and Limonite/Hematite)
Epidote-bearing Rock
Epidote / Silicate mineral aggregate
Limonite/Goethite Nodule
Iron Oxyhydroxide (primarily FeO(OH)·nH2O)
Conglomerate (or Breccia / Porphyry)
Clastic Sedimentary Rock (Conglomerate / Sandstone)
Limonite (Oxidized Iron Ore)
FeO(OH)·nH2O (Hydrous ferric oxide)
Iron-rich mineral fragment, possibly limonite/goethite
Limonite (hydrated iron oxides; commonly goethite, FeO(OH), with hematite)
Not a rock, mineral, or geological specimen
Iron-stained Quartz
Silicon Dioxide (SiO2) with Iron Oxide (Limonite/Goethite) inclusions
Quartz Pebble
Silicon Dioxide (SiO2)
Quartz pebble
Silicon dioxide (SiO2)
Bauxite
Bauxite (mixture of Hydrous Aluminum Oxides)
Chrysocolla (or Turquoise/Aventurine)
Cu2-xAlx(H2-xSi2O5)(OH)4·nH2O
Vein Quartz in Basalt or Mafic Rock
Silicon Dioxide (Quartz veins in volcanic host rock)
Fluorite
Calcium fluoride (CaF2)
Granitic Gneiss
Gneiss (Metamorphic rock predominantly containing quartz, K-feldspar, and plagioclase)
Schist
Mica Schist
Vesicular basalt (scoriaceous basalt)
Basalt, primarily plagioclase, pyroxene, and iron-rich olivine; vesicular variety may be termed scoria
Epidote
Epidote (Ca2(Al, Fe)3(SiO4)3(OH))
Quartz Pebbles
Silicon Dioxide (SiO2)
K2 stone (azurite–granite)
Biotite granite hosting blue azurite (Cu₃(CO₃)₂(OH)₂), often with malachite and quartz
Likely weathered metallic mineral or slag fragment
Indeterminate; possibly iron-rich sulfide/oxide material or industrial slag
Vanadinite
Pb5(VO4)3Cl