Amethyst
Crystalline Silicon Dioxide with Iron impurities (SiO2)
Category
Browse granite specimens identified by the Rock Identifier community.
Amethyst
Crystalline Silicon Dioxide with Iron impurities (SiO2)
Pyrite
Iron Sulfide (FeS2)
Sodalite
Sodalite, Na8(Al6Si6O24)Cl2
Peridot
Olivine ((Mg, Fe)2SiO4)
Amethyst
Silicon Dioxide (SiO2) with iron impurities
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
Orange Calcite
Calcium Carbonate (CaCO3)
Chert (Nodule)
Microcrystalline Quartz (SiO2)
Sandstone
Arenite (SiO2 dominant)
Malachite in Matrix
Copper Carbonate Hydroxide (Cu2CO3(OH)2)
Quartz (Milky/Opaque variety)
Silicon Dioxide (SiO2)
Quartzite
Quartzite (primarily SiO2)
Chert (Arrowhead Artifact)
Microcrystalline or cryptocrystalline Quartz (SiO2)
Porcelain (Kaolin-based)
Alumina silicate ceramic (composed primarily of Kaolinite: Al2Si2O5(OH)4)
Limonite (Iron-rich Siltstone / Sandstone base)
Hydrous ferric oxide mixture (FeO(OH)·nH2O)
Pink Sapphire
Corundum (Al2O3 with Chromium/Titanium/Iron traces)
Gold
Native Gold (Au)
Chert (Jasper variety)
Silicon Dioxide (SiO2)
Basalt
Mafic volcanic rock (Basalt)
Chert (often called Flint)
Cryptocrystalline Quartz (SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Basalt (Greenstone/Trap Rock)
Basalt (dominated by plagioclase feldspar and pyroxene)
Chert (Jasper/Flint variety)
Microcrystalline Quartz (SiO2)
Amethyst (Rough)
Silicon Dioxide with iron impurities (SiO2)
Ferruginous Sandstone (Grit)
Clastic Sedimentary (Ironstone-rich Sandstone)
Amethyst
Silicon Dioxide (SiO2) containing Iron impurities
Sandstone (with Iron Staining)
Clastic Sedimentary Rock (primarily SiO2 with FeO(OH) impurities)
Aventurine
Silicon Dioxide (SiO2) with inclusions
Dragon Stone
Argillaceous Sedimentary Rock (Ohko Stone)
Sandstone (Ferruginous)
Arenite with Iron-Oxide Cement
Aventurine
Silicon Dioxide (SiO2) with inclusions of Fuchsite
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
Amethyst
Amethyst (SiO2 with iron impurities)
Basalt (River Stone)
Extrusive Mafic Igneous Rock (Basalt)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Quartzite
Quartzite (SiO2)
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
Gold Nugget
Native Gold (Au)
Milky Quartz
Silicon Dioxide (SiO2)
Pearl (Biogenic)
Nacre / Calcium Carbonate (CaCO3)
Sandstone (Quartz-rich)
Arenite (composed mainly of SiO2)
Chert Pebble with Quartz Veins
Microcrystalline Quartz (SiO2)