Amethyst Quartz Druse
Silicon Dioxide (SiO2) with iron impurities
Category
Browse industrial byproduct (often mistaken for obsidian or mineral) specimens identified by the Rock Identifier community.
Amethyst Quartz Druse
Silicon Dioxide (SiO2) with iron impurities
Silver (Native Silver/Alloy Specimen)
Ag (Native Silver element), specifically a 90% Ag / 10% Cu alloy
Aquamarine
Beryllium Aluminum Silicate (Be3Al2Si6O18)
Beryl (Emerald Variety)
Beryllium aluminum silicate (Be3Al2Si6O18)
Blue Sapphire
Corundum (Al2O3)
Smoky Quartz
Silicon Dioxide (SiO2)
Peridot (Gem-quality Olivine)
Magnesium Iron Silicate ((Mg, Fe)2SiO4)
Granite
Plutonic Igneous Rock (composed primarily of Quartz, Feldspar, and Mica)
Desert Rose
Gypsum or Barite (CaSO4·2H2O or BaSO4)
Sandstone
Arenite (composed primarily of SiO2)
Asphalt Concrete
Bituminous conglomerate
Quartzite
Quartzite (primarily SiO2)
Basalt with Iron Oxide staining
Mafic Igneous Rock (primarily Plagioclase and Pyroxene)
Peridot (Olivine)
Magnesium Iron Silicate (Mg,Fe)2SiO4
Druzy Quartz (part of a Geode)
Silicon Dioxide (SiO2)
Milky Quartz Pebble
Quartz (Silicon Dioxide - SiO2)
Diamond (in a jewelry setting)
Carbon (C)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Almandine Garnet
Almandine, Fe3Al2(SiO4)3
Sapphire
Corundum (Al2O3)
Chalcedony (specifically Agate or Moonstone-like Quartz)
Silicon Dioxide (SiO2)
Diamond (in jewelry)
Carbon (C)
Black Kyanite
Kyanite (Al2SiO5) with carbonaceous inclusions
Blue Sapphire
Corundum (Al2O3)
Rose Quartz
Silicon dioxide (SiO2)
Blue Sapphire
Corundum (Al2O3 with trace Titanium/Iron)
Pyrite
Iron Disulfide (FeS2)
Quartz Pebble
Silicon Dioxide (SiO2)
Rough Diamond
Diamond (pure carbon, C)
Agate
Agate (Silicon Dioxide - SiO2)
Pyrite
Iron Sulfide (FeS2)
Garnet Schist
Almandine Garnet in Schist (X3Al2(SiO4)3)
Smoky Quartz and Clear Quartz Geode
Silicon Dioxide (SiO2)
Agate
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Marble
Recrystallized Calcite (CaCO3) or Dolomite (CaMg(CO3)2)
Red Jasper (Quartz)
Silicon Dioxide (SiO2) with Iron impurities
Yooperlite
Fluorescent Sodalite-bearing Syenite
Smoky Quartz
Silicon dioxide with aluminum impurities (SiO2)
Rough Garnet in Matrix
Almandine Garnet (Fe3Al2Si3O12)
Anthracite Coal
Anthracite
Milky Quartz Pebble
Silicon Dioxide (SiO2)
Diamond (in a jewelry setting)
Cubic Carbon (C)