Olivine (Peridotite)
Olivine Group; (Mg, Fe)2SiO4
Category
Browse mineral description (anthropogenic material) specimens identified by the Rock Identifier community.
Olivine (Peridotite)
Olivine Group; (Mg, Fe)2SiO4
Sandstone
Arenite (primarily SiO2 - Silicon Dioxide)
Rhodonite
Manganese Silicate (Mn,Fe,Mg,Ca)SiO3
Rose Quartz
Silicon Dioxide with trace elements (SiO2 + Ti, Fe, or Mn)
Rose Quartz
Silicon Dioxide (SiO2) with trace amounts of titanium, iron, or manganese
Rough Emerald (Beryl)
Emerald (Be3Al2(SiO3)6 with Cr/V impurities)
Mica Schist
Mica Schist (KAl2(AlSi3O10)(OH)2 / K(Mg,Fe)3AlSi3O10(OH)2)
Ferruginous Sandstone (Ironstone Nodules)
Ferruginous Sandstone with Limonite/Goethite coating (Fe2O3·H2O)
Petrified Wood
Silicified wood (Quartz variant, SiO2)
Petrified Wood (Silicified Wood)
Silicified Paleoflora (mainly Quartz, SiO2)
Petrified Wood
Silicified Wood (SiO2)
Sodalite
Sodalite (Na8(Al6Si6O24)Cl2)
Quartz
Silicon Dioxide (SiO2)
Quartz
Silicon dioxide (SiO2)
Milky Quartz with Iron Staining
Quartz (Silicon Dioxide, SiO2)
Schist
Mica Schist (Medium-grade Metamorphic Rock)
Sandstone (Banded)
Clastic Sedimentary Rock (primarily SiO2)
Sandstone (Ferruginous)
Arenite (primarily SiO2 with Fe2O3 staining)
Quartz Geode/Cluster
Quartz (SiO2)
Red Jasper
Red Jasper (variety of Chalcedony, SiO₂)
Chert (varieties: Flint or Chalcedony)
Microcrystalline Quartz (SiO2)
Goldstone (Red)
Aventurine Glass (Cupriferous glass)
Bituminous Coal (with Anthracite or Vitrinite inclusion)
Organic-rich Sedimentary Rock (Carboniferous classification)
Fulgurite
Fulgurite (Lechatelierite), amorphous SiO2
Conglomerate
Conglomerate (Clastic Sedimentary Rock)
Greywacke (River Pebble)
Greywacke sandstone with quartz veining
Mica Schist
Foliated Metamorphic Rock (rich in Muscovite or Biotite)
Ferruginous Sandstone
Arenite with Iron Oxide matrix (Fe2O3)
Sandstone (with Iron Staining)
Arenite (composed primarily of SiO2 with Fe2O3 staining)
Sandstone (specifically Cross-bedded Sandstone)
Arenite (composed primarily of SiO2)
Red Sandstone
Arenite (predominantly SiO2 with Fe2O3)
Ironstone Concretion / Goethite-Hematite Nodule
Goethite/Hematite (α-FeO(OH) / Fe2O3)
Black Tourmaline
Schorl (Na(Fe²⁺)₃Al₆(OH)₄(BO₃)₃Si₆O₁₈)
Pyrite (Fool's Gold)
Iron Disulfide (FeS2)
Diamond
Carbon (C)
Fossiliferous Limestone
Biogenic Limestone (Calcium Carbonate, CaCO3)
Banded Onyx (Cave Calcite)
Calcite (CaCO3), often called Mexican Onyx or Travertine
Diorite
Intrusive Igneous Rock (Intermediate Composition)
Quartz (Iron-stained)
Silicon Dioxide (SiO2) with Hematite/Limonite impurities
Granodiorite
Granodiorite (Na,Ca)(Si,Al)4O8
Red Sandstone
Arenite (primarily Quartz with Hematite cement)
Sandstone (Quartz-rich Pebble)
Arenite (primarily SiO2)