Greenstone (possibly Basalt or Greenschist)
Greenschist (composed primarily of chlorite, actinolite, and epidote)
Category
Browse igneous or metamorphic (base stone); anthropogenic (decoration) specimens identified by the Rock Identifier community.
Greenstone (possibly Basalt or Greenschist)
Greenschist (composed primarily of chlorite, actinolite, and epidote)
Anthracite Coal
Anthracite (high-rank coal / Carbon)
Blue Moss Agate
Silicon Dioxide (SiO2) with mineral inclusions
Limonitic Gossan
Goethite/Limonite aggregate after sulfide
River Stone / Siltstone
Siltstone (composed of lithified silt)
Sandstone
Arenite (SiO2 based with mineral cement)
Breccia
Breccia
Sandstone
Arenite (primarily SiO2)
Granite Thin Section
Granitic rock (Phaneritic texture)
Quartz (Milky/Iron-stained)
Silicon Dioxide (SiO2)
Moonstone
Orthoclase/Albite (KAlSi3O8 / NaAlSi3O8) with Adularescence
Blue Sapphire
Corundum (Al2O3)
Chert (specifically Gray/Tan Chert Node)
Microcrystalline Quartz (SiO2)
Lapis Lazuli
Lapis Lazuli (a rock, not a single mineral; primary mineral is Lazurite (Na,Ca)8(AlSiO4)6(S,SO4,Cl)1-2
Basalt with Plagioclase Phenocrysts
Porphyritic Basalt
Garnet (Almandine)
Almandine (Fe3Al2(SiO4)3)
Magnetite
Magnetite (Fe3O4)
Clear Quartz
Silicon Dioxide (SiO2)
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
Dumortierite Quartz
Dumortierite-bearing Quartz (Al7BO3(SiO4)3O3)
Basalt with Caliche Crust
Aphanitic Mafic Igneous Rock with Calcium Carbonate (CaCO3) coating
Basalt
Mafic Igneous Rock (primarily Plagioclase and Pyroxene)
Basalt (Vesicular)
Basalt (Extrusive Mafic Igneous Rock)
Marble
Marbles are primarily composed of calcite (calcium carbonate, CaCO3) or dolomite (calcium magnesium carbonate, CaMg(CO3)2).
Basalt
Basalt
Aventurine
Quartz (Aventurine variety)
Fossiliferous Limestone
CaCO3 (principally Calcite or Aragonite)
Quartz Pebble (Sea Glass-like Quartz)
Quartz (Silicon Dioxide - SiO2)
Quartz (Common or Milky)
Silicon Dioxide (SiO2)
Jasper
Silicon Dioxide (SiO2)
Nuummite
Nuummite (Orthoamphibole rock composed of Anthophyllite and Gedrite)
Slickenside
Tectonic Fault Scarp Surface
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
Quartz (Milky/Common)
Silicon Dioxide (SiO2)
Sugilite
KNa2(Fe,Mn,Al)2Li3Si12O30 (Potassium Sodium Lithium Iron Manganese Aluminum Silicate)
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
Rough Sapphire
Corundum (Al2O3)
Milky Quartz
Silicon Dioxide (SiO2)
Quartz
Silicon Dioxide (SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Smoky Quartz
Silicon Dioxide (SiO2)
Smoky Quartz
Smoky Quartz (Silicon Dioxide - SiO2)