Amethyst (Tumbled Stone)
Amethyst (Silicon Dioxide with Iron impurities, SiO2)
Category
Browse mineral, often found as a rock (metamorphic) specimens identified by the Rock Identifier community.
Amethyst (Tumbled Stone)
Amethyst (Silicon Dioxide with Iron impurities, SiO2)
Garnet
Garnet Group (often Pyrope or Almandine); X3Y2(SiO4)3
Pegmatite
Coarse-grained Igneous Rock (Granitic Pegmatite)
Quartz Geode
Silicon Dioxide (SiO2) in Geode form
Mica (Muscovite)
Potassium aluminum silicate - KAl2(AlSi3O10)(OH)2
Peacock Ore
Bornite (Cu5FeS4) or Chalcopyrite treated with acid
Sandstone
Arenite (composed primarily of SiO2)
Pink Quartzite
Quartzite (SiO2)
Pink Granite Gneiss
Granitic Gneiss
Gneiss (Granitic Gneiss)
Gneiss (composed primarily of Quartz, Feldspar, and Mica/Amphibole)
Citrine Geode Fragment
Citrine (Silicon Dioxide with Iron Impurities), SiO2
Rhodochrosite in Quartz
Manganese Carbonate (MnCO3)
Amethyst
Silicon Dioxide (SiO2) with iron impurities
Basalt with Plagioclase Phenocrysts
Porphyritic Basalt
Vesicular Basalt with Amygdaloidal Infill
Basalt (Mafic Extrusive Igneous Rock)
Quartzite with Iron Inclusions
Metamorphosed Quartz Sandstone (SiO2 with Fe2O3)
Chlorite Included Quartz
Silicon Dioxide (SiO2) with Chlorite (Mg,Fe,Li)6AlSi3O10(OH)8
Gneiss
Gneiss
Pyrite (on Quartz/Sulfide matrix)
Iron Sulfide (FeS2)
Quartz Crystal Cluster
Silicon Dioxide (SiO2)
Citrine
Silicon Dioxide (SiO2) with iron impurities
Gneiss
Gneiss (High-grade Regional Metamorphic Rock)
Quartz
Silicon Dioxide (SiO2)
Graywacke
Lithic Sandstone (Graywacke)
Shale or Argillite
Shale (fine-grained clastic sedimentary rock) or Argillite (low-grade metamorphic rock derived from shale)
Sandstone
Clastic sedimentary rock (primarily SiO2)
Amygdaloidal Basalt
Amygdaloidal Basalt (Mafic Volcanic Rock)
Asphalt (Road Aggregate)
Asphalt concrete / Bituminous mixture
Quartzite
Quartzite (High-purity SiO2)
Quartzite Pebble
Quartzite (primarily SiO2)
Sandstone
Arenite (predominantly Quartz Sandstone)
Concretion with Quartz Veining
Septarian Concretion (CaCO3 / SiO2)
Smoky Quartz
Silicon Dioxide (SiO2)
Smoky Quartz
Silicon Dioxide (SiO2)
Sandstone
Arenite (primarily SiO2)
Garnet
Garnet Group (Silicate mineral); general formula X3Y2(SiO4)3
Quartz / Quartzite Pebble
Silicon Dioxide (SiO2)
Sandstone
Arenite (SiO2 primarily)
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
Pyrite in Shale
Iron Disulfide (FeS2)
Fairy Stone (Staurolite)
Staurolite (Fe2+2Al9Si4O22(OH)2)
Rainbow Moonstone with Black Tourmaline
White Labradorite with Schorl (Na,Ca)(Al,Si)4O8