Sandstone (with potential iron-oxide staining)
Arenite (primarily SiO2)
Category
Browse mineral (synthetic) specimens identified by the Rock Identifier community.
Sandstone (with potential iron-oxide staining)
Arenite (primarily SiO2)
Snowflake Obsidian
Volcanic glass containing Cristobalite (SiO2)
Iron Meteorite (Individual)
Siderite (composed of Kamacite and Taenite minerals)
Dalmation Stone
Peralkaline Rock (mixed silicate minerals)
Ammonite Fossil (Polished Section)
Ammonoidea (typically mineralized with Calcite CaCO3)
Greenschist (Greenstone)
Greenschist
Granite (including Pegmatite variants)
Phaneritic Plutonic Rock (composed primarily of Quartz SiO2, Feldspar KAlSi3O8, and Biotite/Muscovite mica)
Shale or Argillite
Shale (fine-grained clastic sedimentary rock) or Argillite (low-grade metamorphic rock derived from shale)
Sandstone
Arenite (Sedimentary rock composed of sand-sized grains, primarily SiO2)
Gneiss
Gneiss (High-grade Metamorphic Rock)
Sandstone
Arenite (predominantly SiO2)
Greenschist (Greenstone River Pebble)
Greenschist (Chlorite Schist)
Blue Quartzite
Quartzite (specifically a variety enriched with blue-coloring minerals)
Dinosaur Bone (Fossilized)
Permineralized Bone (CaCO3 or SiO2 after Hydroxylapatite)
Labradorite
Labradorite (a calcium-enriched feldspar mineral), (Ca, Na)(Al, Si)4O8
Red Garnet
Almandine and Pyrope (Silicate minerals: Fe3Al2(SiO4)3 and Mg3Al2(SiO4)3)
Nephrite (a form of Jade)
Nephrite (a variety of the mineral actinolite, Ca2(Mg,Fe)5Si8O22(OH)2)
Limonite-pseudomorph after Pyrite (Prophecy Stone)
Goethite and Limonite secondary minerals (FeO(OH)·nH2O) replacing Pyrite (FeS2)
Granite
Granite (a plutonic igneous rock composed of quartz, feldspar, and mica)
Quartz with Hematite Staining
Silicon Dioxide (SiO2) with Ferric Oxide (Fe2O3) inclusions
Diamond
Carbon (C)
Lepidolite
K(Li,Al)3(Al,Si,Rb)4O10(F,OH)2
Diamond
Diamond (C)
Granite
Phaneritic Felsic Igneous Rock (Main minerals: SiO2, KAlSi3O8, NaAlSi3O8)
Green Aventurine
Aventurine (variety of Quartz - SiO2)
Schist
Crystalline Metamorphic Rock (Schistose)
Basalt (with possible mineral veining)
Basalt (Aphanitic Mafic Igneous Rock)
Quartzite with Iron Mineral Banding
Silicon Dioxide (SiO2) with Ferric Oxide (Fe2O3) staining
Petrified Wood
Silicified wood (primarily Silicon Dioxide, SiO2)
Ferruginous Sandstone
Sandstone (rich in iron oxides/hydroxides)
Fluorite
Calcium Fluoride (CaF2)
Green Aventurine
Quartz with Fuchsine inclusions (SiO2 + K(Al,Cr)2AlSi3O10(OH)2)
Geode (Unopened)
Silica Concretion / Geode (Formula: SiO2 for quartz internal contents)
Chrysocolla
Chrysocolla, (Cu, Al)2H2Si2O5(OH)4·nH2O
Howlite and Purpurite druzy
Calcium Borosilicate Hydroxide (Howlite) and Manganese Phosphate (Purpurite)
Tumbled Moonstone
Feldspar (Orthoclase/Albite), KAlSi3O8
Turquoise
CuAl6(PO4)4(OH)8·4H2O (Hydrous phosphate of copper and aluminium)
Quartz Geode
Silicon Dioxide (SiO2)
Satin Spar (often sold as Selenite)
Gypsum (CaSO4·2H2O)
Sandstone
Arenite (SiO2 primarily)
Granite Cobble
Granite
Basalt with Quartz/Feldspar Vein
Amygdaloidal Basalt with Plutonic intrusion (SiO2/KAlSi3O8)