Amethyst
Amethyst (Silicon Dioxide, SiO2 + Fe4+ impurities)
Category
Browse man made specimens identified by the Rock Identifier community.
Amethyst
Amethyst (Silicon Dioxide, SiO2 + Fe4+ impurities)
Rose Gold (Copper-Gold Alloy)
Aurum-Cuprum Alloy (Au-Cu)
Chert (and Flint)
Silicon Dioxide (SiO2)
Chert (specifically White Chert or Novaculite)
Silicon Dioxide (SiO₂)
Green Slag Glass
Amorphous Silica / Glassy Blast Furnace Slag
Pyrite
Iron Sulfide (FeS2)
Pyrite in Matrix
Iron Sulfide (FeS2)
Chert with Limestone
Silicon Dioxide (SiO2) in Calcium Carbonate (CaCO3) Matrix
Chert (Tan/Brown variety)
Chert (Silicon Dioxide, SiO2)
Industrial Slag
Anthropogenic Vitreous Slag
Chert (Nodule)
Chert (SiO2)
Amber
Succinite (Carbon-based organic compound; approximate formula C10H16O)
Chert (specifically Jasper or Flint variety)
Cryptocrystalline Quartz (SiO2)
Chert (Flint)
Chert (Microcrystalline Quartz, SiO2)
Petrified Wood
Silicified Wood (primarily SiO2)
Coquina
Biogenic Limestone (Calcite/Aragonite base, CaCO3)
Chert (and Flint)
Silicon Dioxide (SiO2)
Chert (specifically White Chert or Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Red Jasper
Silicon Dioxide (SiO2) with Hematite inclusions
Pyrite
Iron Disulfide (FeS2)
Chert (Jasper/Agate variety)
Silicon Dioxide (SiO2)
Banded Calcite (often sold as 'Mexican Onyx' or 'Green Onyx')
Calcite (Calcium Carbonate, CaCO3)
Moonstone
Orthoclase Feldspar (formula: (K,Na)AlSi3O8)
Chert
Microcrystalline Quartz (SiO2)
Diamond (as set in a metal alloy ring)
Diamond (Pure Carbon, C)
Chert (often called Flint)
Microcrystalline Quartz (SiO2)
Chert (Jasper variety)
Silicon Dioxide (SiO2)
Fossilized Shark Tooth
Carcharocles sp. or Striatolamia sp. (Phosphate/Carbonate mineralized Hydroxyapatite)
Grey Granite
Phaneritic Felsic Intrusive Igneous Rock
Pearl (Biogenic)
Nacre / Calcium Carbonate (CaCO3)
Obsidian
Volcanic Glass (Amorphous SiO2)
Sandstone (Red/Brown Variety)
Arenite (composed primarily of SiO2 with Fe2O3 iron oxide inclusions)
Sunstone
Aventurine Feldspar (Plagioclase Feldspar with inclusions)
Diamond
Carbon (C)
Pyrite
Iron Sulfide (FeS2)
Goldstone and Aura Quartz
Cuprous Glass (Goldstone) and Titanium-coated SiO2 (Aura Quartz)
Granite
Phaneritic Igneous Rock (primarily Quartz, Feldspar, and Mica)
Granite
Phaneritic Igneous Rock (composed mostly of Quartz, Alkali Feldspar, and Plagioclase)
Granite
Phaneritic plutonic rock (SiO2 typically >69%)
Chert (Chocolate or Brown Flint)
Chert (SiO2)
Quartzite Pebble
Quartzite (SiO2)
Chert (Jasper/Agate variety)
Microcrystalline Quartz (SiO2)