Pyrite (Fool's Gold)
Iron Disulfide (FeS2)
Category
Browse mineral (silicate replaced organic material) specimens identified by the Rock Identifier community.
Pyrite (Fool's Gold)
Iron Disulfide (FeS2)
Ferruginous Sandstone (Ironstone Nodules)
Ferruginous Sandstone with Limonite/Goethite coating (Fe2O3·H2O)
Diorite (River Cobble)
Intrusive Igneous Diorite
Amber
Succinite (fossilized resin)
Diamond
Cubic Carbon (C)
Diamond (as set in a gold ring)
Carbon (C)
Diamond
Carbon (C)
Lapis Lazuli
Lapis lazuli (a rock primarily composed of Lazurite, (Na,Ca)8(AlSiO4)6(S,Cl,SO4,OH)2)
Greenschist
Greenschist (Chlorite Schist)
Pyrite
Iron Sulfide (FeS2)
Quartz (Milky or White Quartz)
Silicon Dioxide (SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Pyrite
Iron Sulfide (FeS2)
Rough Aquamarine
Beryl (Be₃Al₂Si₆O‑₁•H₂O)
Blue Calcite
Calcite (Calcium Carbonate, CaCO3)
Quartz (Milky/Smoky variety)
Silicon Dioxide (SiO2)
Dragon Blood Jasper
Epidote-rich Quartzite (SiO2 with Ca2(Al,Fe)3(SiO4)3(OH))
Pearl (nacre)
Calcium Carbonate (mostly CaCO3 as Aragonite) and Conchiolin
Rose Quartz
Silicon Dioxide (SiO2) with trace amounts of titanium, iron, or manganese
Garnet (Almandine)
Almandine (Fe3Al2(SiO4)3)
Conglomerate
Conglomerate (clastic sedimentary rock)
Green Aventurine
Aventurine Quartz (SiO2 with Fuchsite inclusions)
Ironstone Concretion / Goethite-Hematite Nodule
Goethite/Hematite (α-FeO(OH) / Fe2O3)
Shale
Mudstone (composed primarily of clay minerals like kaolinite, illite, and smectite, with quartz and calcite)
Aragonite Star Cluster
Aragonite (Calcium Carbonate - CaCO3)
Milky Quartz
Silicon Dioxide (SiO2)
Sandstone
Arenite (primarily SiO2 - Silicon Dioxide)
Sandstone (Ferruginous)
Arenite (primarily SiO2 with Fe2O3 staining)
Quartz (Iron-stained)
Silicon Dioxide (SiO2) with Hematite/Limonite impurities
Granite
Phaneritic Felsic Igneous Rock
Green Onyx (Banded Calcite)
Travertine (CaCO3 - Calcium Carbonate)
Lepidolite
Lepidolite (K(Li,Al)3(Al,Si,Rb)4O10(F,OH)2)
Granite
Granite (Felsic Plutonic Rock)
Granite (Weathered)
Course-grained Intrusive Igneous Rock
Siltstone with Quartz Vein
Siltstone (primarily SiO2, Al2O3, Fe2O3)
Banded Onyx (Cave Calcite)
Calcite (CaCO3), often called Mexican Onyx or Travertine
Sandstone with Liesegang Rings
Arenite with Iron Oxide Liesegang Banding
Sandstone (Quartz Sandstone)
Clastic sedimentary rock (primarily SiO2)
Shale with Plant Fossils / Carbonaceous Shale
Laminated Mudrock (Siliciclastic)
Limonite Pseudomorph after Pyrite
Limonite (Hydrous iron oxides, FeO(OH)·nH2O) replacing Pyrite (FeS2)
Rose Quartz
Silicon Dioxide (SiO2) with trace amounts of titanium, iron, or manganese
Cullet Glass (Industrial Slag Glass)
Amorphous Silica (SiO2) with metallic oxide impurities