Rock Identifier

Category

Organic Gemstone (Not A Rock Or Mineral)

Browse organic gemstone (not a rock or mineral) specimens identified by the Rock Identifier community.

Sandstone with Quartz Vein (Arenite with SiO2 intrusion) — sedimentary

Sandstone with Quartz Vein

Arenite with SiO2 intrusion

Green Aventurine (Silicon Dioxide (SiO2) with inclusions of Fuchsite (K(Al,Cr)2(AlSi3O10)(OH)2)) — metamorphic

Green Aventurine

Silicon Dioxide (SiO2) with inclusions of Fuchsite (K(Al,Cr)2(AlSi3O10)(OH)2)

Limestone (Concretionary or Tufa) (Calcium Carbonate (CaCO3)) — sedimentary

Limestone (Concretionary or Tufa)

Calcium Carbonate (CaCO3)

Quartz (likely Milky Quartz) (Quartz (SiO₂ - Silicon Dioxide)) — Mineral

Quartz (likely Milky Quartz)

Quartz (SiO₂ - Silicon Dioxide)

Agate (Common Chalcedony) (Silicon Dioxide (SiO2)) — mineral

Agate (Common Chalcedony)

Silicon Dioxide (SiO2)

Sandstone (Painted) (Arenite (primarily SiO2)) — sedimentary

Sandstone (Painted)

Arenite (primarily SiO2)

Serpentine (Greenstone) (Antigorite, Lizardite, and Chrysolite mixture (Mg3Si2O5(OH)4)) — metamorphic

Serpentine (Greenstone)

Antigorite, Lizardite, and Chrysolite mixture (Mg3Si2O5(OH)4)

Bloodstone (Heliotrope (a variety of Chalcedony, SiO₂ with inclusions)) — Metamorphic Rock

Bloodstone

Heliotrope (a variety of Chalcedony, SiO₂ with inclusions)

Metamorphic Rock

Chert (Flint) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Petrified Wood (Silicified Wood (SiO2)) — mineral

Petrified Wood

Silicified Wood (SiO2)

Emerald (Faceted Gemstone) (Beryl (Be3Al2Si6O18 with Chromium/Vanadium impurities)) — mineral

Emerald (Faceted Gemstone)

Beryl (Be3Al2Si6O18 with Chromium/Vanadium impurities)

Sandstone (lithic wacke) (Arenite / Lithic Wacke (mostly SiO2 with rock fragments)) — sedimentary

Sandstone (lithic wacke)

Arenite / Lithic Wacke (mostly SiO2 with rock fragments)

Sandstone (likely Greywacke or Lithic Sandstone) (Arenite / Wacke) — sedimentary

Sandstone (likely Greywacke or Lithic Sandstone)

Arenite / Wacke

Chert (often found as Flint) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (often found as Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Chert (Flint variety) (Microcrystalline or cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Flint variety)

Microcrystalline or cryptocrystalline Quartz (SiO2)

Sandy Ironstone (Ferruginous Sandstone) — sedimentary

Sandy Ironstone

Ferruginous Sandstone

Graphite (Graphite (Chemical Formula: C)) — Mineral (Native Element)

Graphite

Graphite (Chemical Formula: C)

Mineral (Native Element)

Serpentinite (Serpentinite (complex silicate minerals including lizardite, chrysotile, and antigorite: (Mg,Fe)3Si2O5(OH)4)) — metamorphic

Serpentinite

Serpentinite (complex silicate minerals including lizardite, chrysotile, and antigorite: (Mg,Fe)3Si2O5(OH)4)

Fossilized Shark Tooth (Basal Bone) (Otodus sp. (Mineralized Hydroxyapatite)) — sedimentary

Fossilized Shark Tooth (Basal Bone)

Otodus sp. (Mineralized Hydroxyapatite)

Basalt with Quartz Vein (Mafic Igneous Rock (SiO2 filling)) — igneous

Basalt with Quartz Vein

Mafic Igneous Rock (SiO2 filling)

Shale (Lutaceous sedimentary rock) — sedimentary

Shale

Lutaceous sedimentary rock

Moss Agate (Silicon Dioxide (SiO2) with inclusions of hornblende, chlorite, or manganese/iron oxides) — mineral

Moss Agate

Silicon Dioxide (SiO2) with inclusions of hornblende, chlorite, or manganese/iron oxides

Amazonite (Potassium Feldspar (KAlSi3O8)) — Mineral

Amazonite

Potassium Feldspar (KAlSi3O8)

Quartz Vein in Host Rock (Hydrothermal Quartz (SiO2) in Slates/Schists) — metamorphic

Quartz Vein in Host Rock

Hydrothermal Quartz (SiO2) in Slates/Schists

Chert (Flint) (Chert (Silicon Dioxide, SiO2)) — sedimentary

Chert (Flint)

Chert (Silicon Dioxide, SiO2)

Chalcedony Geode (Chalcedony (SiO2) within a geode structure) — Mineral Geode/Sedimentary or Volcanic related

Chalcedony Geode

Chalcedony (SiO2) within a geode structure

Mineral Geode/Sedimentary or Volcanic related

Chrysoprase (Chalcedony (cryptocrystalline quartz) with nickel inclusions; SiO2) — Mineral

Chrysoprase

Chalcedony (cryptocrystalline quartz) with nickel inclusions; SiO2

Chert (Jasper/Flint variety) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Jasper/Flint variety)

Microcrystalline Quartz (SiO2)

Sapphire (Corundum (Al₂O₃) with trace elements causing color variations.) — Mineral

Sapphire

Corundum (Al₂O₃) with trace elements causing color variations.

Amber (Succinurite (C10H16O)) — mineraloid

Amber

Succinurite (C10H16O)

Petrified Wood (Silicified Wood (SiO2 permineralization)) — sedimentary

Petrified Wood

Silicified Wood (SiO2 permineralization)

Chert (often called Flint when in chalk or limestone) (Silicon Dioxide (SiO₂)) — sedimentary

Chert (often called Flint when in chalk or limestone)

Silicon Dioxide (SiO₂)

Ruby (Corundum (Al₂O₃) with Chromium (Cr)) — Mineral (gemstone)

Ruby

Corundum (Al₂O₃) with Chromium (Cr)

Mineral (gemstone)

White Quartz (Quartz (SiO2)) — Mineral

White Quartz

Quartz (SiO2)

Dinosaur Fossil (Skull) (Dinosauria fossilis (Petrified Hydroxyapatite / Calcium Carbonate)) — sedimentary

Dinosaur Fossil (Skull)

Dinosauria fossilis (Petrified Hydroxyapatite / Calcium Carbonate)

Petrified Wood (Silicified Wood (primarily SiO2)) — sedimentary

Petrified Wood

Silicified Wood (primarily SiO2)

Petrified Wood (Silicified wood (primarily Quartz/Chalcedony, SiO2)) — metamorphic

Petrified Wood

Silicified wood (primarily Quartz/Chalcedony, SiO2)

Fossilized Shark Tooth (Fragment) (Elasmobranchii fossil (likely Cretalamna or Squalicorax genus)) — sedimentary

Fossilized Shark Tooth (Fragment)

Elasmobranchii fossil (likely Cretalamna or Squalicorax genus)

Yellow Sapphire or Citrine (Al2O3 (Corundum) or SiO2 (Quartz)) — mineral

Yellow Sapphire or Citrine

Al2O3 (Corundum) or SiO2 (Quartz)

Petrified Wood (Silicified Wood (SiO2)) — sedimentary

Petrified Wood

Silicified Wood (SiO2)

Dearest Jewelry (Multigemstone) (Combination of Diamond (C), Emerald (Be3Al2Si6O18), Amethyst/Rock Crystal (SiO2), Ruby (Al2O3), Emerald (Be3Al2Si6O18), Sapphire (Al2O3), and Topaz (Al2SiO4(F,OH)2)) — Mineral

Dearest Jewelry (Multigemstone)

Combination of Diamond (C), Emerald (Be3Al2Si6O18), Amethyst/Rock Crystal (SiO2), Ruby (Al2O3), Emerald (Be3Al2Si6O18), Sapphire (Al2O3), and Topaz (Al2SiO4(F,OH)2)

Sandstone (Graywacke) (Clastic Sedimentary Rock (Lithic Sandstone)) — sedimentary

Sandstone (Graywacke)

Clastic Sedimentary Rock (Lithic Sandstone)