Serpentine
Serpentine-group ((Mg,Fe,Ni,Al,Zn,Mn)3(Si,Al,Fe)2O5(OH)4)
metamorphic
Category
Mineral, Often A Rock Given Its Aggregate Nature
Browse mineral, often a rock given its aggregate nature specimens identified by the Rock Identifier community.
Man-made Synthetic Material (Costume Faux Fur)
Synthetic Polymer (Polyester/Acrylic)
not a rock
Aqua Aura Quartz
Titanium/Gold-coated Silicon Dioxide (SiO2)
mineral
Geode (Quartz)
Silicon Dioxide (SiO2)
mineral
Turquoise
Hydrous phosphate of copper and aluminium (CuAl6(PO4)4(OH)8·4H2O)
mineral
Sandstone (Ferruginous)
Sandstone (Clastic sedimentary rock, predominantly SiO2 with Fe2O3 cement)
sedimentary
Yellow Jasper
Jasper (Silicon Dioxide, SiO2)
sedimentary
Amethyst (Chevron or Banded Amethyst)
Silicon Dioxide (SiO2) with iron impurities
mineral
Sandstone (likely Iron-rich or Arkosic)
Arenite (SiO2 with FeO(OH) or Fe2O3 staining)
sedimentary
Sandstone
Arenite (primarily SiO2)
sedimentary
Quartz Geode
Silicon Dioxide (SiO2)
mineral
Sandstone
Arenite (primarily Quartz, SiO2)
sedimentary
Chert (Iron-Stained)
Microcrystalline Silica (SiO2)
sedimentary
Limonite (Iron Ore)
Limonite (FeO(OH)·nH2O)
Mineral
Ruby in Kyanite
Al2O3 (Corundum) in Al2SiO5 (Kyanite-Fuchsite-Quartz)
metamorphic
Chalcedony (Botryoidal Agate vein)
Chalcedony (Microcrystalline Quartz) - SiO2
mineral
Shale
Mudstone (composed primarily of clay minerals like kaolinite, illite, and smectite, with quartz and calcite)
sedimentary
Rose Quartz
Silicon Dioxide (SiO2) with trace amounts of titanium, iron, or manganese
mineral
Mica Schist
Mica Schist (primarily Muscovite or Biotite KAl2(AlSi3O10)(OH)2)
metamorphic
Quartz vein in Host Rock
Crystalline Silicon Dioxide (SiO2) in Lithic Matrix
metamorphic
Sandstone (with Iron concretions/staining)
Arenite (composed primarily of Quartz and Feldspar with Iron Oxide cement)
sedimentary
Basalt
Extrusive mafic igneous rock
igneous
Dalmatian Jasper
Peralkaline rhyolite with Arfvedsonite inclusions
igneous
Sandstone
Arenite (primarily SiO2)
sedimentary
Prehnite
Prehnite Ca2Al2Si3O10(OH)2
mineral
Red Garnet
Garnet Group (e.g., Pyrope, Almandine, Spessartine, Grossular, Andradite, Uvarovite)
Mineral
Greywacke
Dirty Sandstone (Lithic wacke)
sedimentary
Ferruginous Quartz
Quartz (Silicon Dioxide) with Iron Inclusion, SiO2
mineral
Limonite Concretion
Goethite-rich Concretion (FeO(OH))
sedimentary
Quartz / Common Agate
Silicon Dioxide (SiO2)
mineral
Dalmatian Jasper (Dalmatian Stone)
Perthitic feldspar with Arfvedsonite inclusions
igneous
Sandstone
Clastic sedimentary rock (primarily SiO2)
sedimentary
Sandstone Concretion
Septarian or Carbonate-cemented Sandstone Concretion
sedimentary
Basalt with Quartz/Calcite Vein
Basalt (Mafic Volcanic Rock with secondary mineralization)
igneous
Asphalt Concrete
Bituminous Concrete / Asphaltic Composite
not a natural rock (man-made composite)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
mineral
Basalt
Basalt
Igneous
Basalt
Vesicular Basalt
igneous
Pegmatite
Coarse-grained Igneous Rock (Granitic Pegmatite)
igneous
Specular Hematite
Iron Oxide (Fe2O3)
mineral
Milky Quartz with Iron Staining
Quartz (Silicon Dioxide, SiO2)
mineral
River Cobble (likely Basalt or Chert)
Siliceous River Rock / Microcrystalline Quartz / Mafic Igneous
igneous/sedimentary