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.

Turquoise (Hydrated phosphate of copper and aluminium: CuAl6(PO4)4(OH)8·4H2O) — Mineral

Turquoise

Hydrated phosphate of copper and aluminium: CuAl6(PO4)4(OH)8·4H2O

Chert (often called Jasper or River Rock) (Chert (SiO2)) — sedimentary

Chert (often called Jasper or River Rock)

Chert (SiO2)

Chert (specifically Flint or Novaculite variant) (Chert (Microcrystalline Quartz, SiO2)) — sedimentary

Chert (specifically Flint or Novaculite variant)

Chert (Microcrystalline Quartz, SiO2)

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

Petrified Wood

Silicified Wood (primarily SiO2)

Quartz (on matrix) (Quartz (Silicon Dioxide, SiO₂)) — Mineral

Quartz (on matrix)

Quartz (Silicon Dioxide, SiO₂)

Carnelian (Carnelian (Silicon Dioxide - SiO2)) — mineral

Carnelian

Carnelian (Silicon Dioxide - SiO2)

Quartz Pebble (Milky Quartz) (Silicon Dioxide (SiO2)) — mineral

Quartz Pebble (Milky Quartz)

Silicon Dioxide (SiO2)

Moonstone (Orthoclase Feldspar (composed of alternate layers of orthoclase and albite), (K,Na)AlSi3O8) — mineral

Moonstone

Orthoclase Feldspar (composed of alternate layers of orthoclase and albite), (K,Na)AlSi3O8

Chert / Jasper / Agate (Chalcedony Group) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert / Jasper / Agate (Chalcedony Group)

Microcrystalline Quartz (SiO2)

Petrified Wood (Silicified Wood (SiO2)) — sedimentary

Petrified Wood

Silicified Wood (SiO2)

Chert (Chert / Flint) (Silicon dioxide (SiO2) - Microcrystalline quartz) — sedimentary

Chert (Chert / Flint)

Silicon dioxide (SiO2) - Microcrystalline quartz

Chert (Nodule) (Silicon Dioxide (SiO2)) — sedimentary

Chert (Nodule)

Silicon Dioxide (SiO2)

Sodalite (Sodalite - Na8(Al6Si6O24)Cl2) — mineral

Sodalite

Sodalite - Na8(Al6Si6O24)Cl2

Amethyst (Silicon dioxide (SiO2) with iron impurities) — mineral

Amethyst

Silicon dioxide (SiO2) with iron impurities

Bloodstone (also known as Heliotrope) (Silicon Dioxide (SiO2) - variety of Chalcedony) — mineral

Bloodstone (also known as Heliotrope)

Silicon Dioxide (SiO2) - variety of Chalcedony

Sodalite (Na8(Al6Si6O24)Cl2) — mineral

Sodalite

Na8(Al6Si6O24)Cl2

Carnelian (Agate) (SiO2 (Silicon Dioxide with Iron Oxide impurities)) — mineral

Carnelian (Agate)

SiO2 (Silicon Dioxide with Iron Oxide impurities)

Smoky Quartz (Silicon Dioxide (SiO2)) — mineral

Smoky Quartz

Silicon Dioxide (SiO2)

Smoky Quartz Cluster (Smoky Quartz (Silicon Dioxide - SiO2)) — mineral

Smoky Quartz Cluster

Smoky Quartz (Silicon Dioxide - SiO2)

Petrified Wood (Silicified Wood (SiO2)) — metamorphic

Petrified Wood

Silicified Wood (SiO2)

Quartz / Quartzite (Silicon Dioxide (SiO2)) — mineral / metamorphic

Quartz / Quartzite

Silicon Dioxide (SiO2)

mineral / metamorphic

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

Chert (variant Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Carnelian (Carnelian Chalcedony (SiO2 with iron oxide impurities)) — mineral

Carnelian

Carnelian Chalcedony (SiO2 with iron oxide impurities)

Crinoid Fossil in Limestone (Crinoid (Class Crinoidea) in Fossiliferous Limestone (CaCO3)) — sedimentary

Crinoid Fossil in Limestone

Crinoid (Class Crinoidea) in Fossiliferous Limestone (CaCO3)

Chert (variously identified as Flint) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (variously identified as Flint)

Microcrystalline Quartz (SiO2)

Garnet (Almandine (Fe3Al2(SiO4)3)) — mineral

Garnet

Almandine (Fe3Al2(SiO4)3)

Chert (Quartz Variety) (Chert (mostly SiO2 / Silicon Dioxide)) — sedimentary

Chert (Quartz Variety)

Chert (mostly SiO2 / Silicon Dioxide)

Pyrite in Shale (Iron Disulfide (FeS2) in Argillaceous Shale) — sedimentary

Pyrite in Shale

Iron Disulfide (FeS2) in Argillaceous Shale

Pink Tourmaline (Rubellite) (Elbaite (Tourmaline group) - Na(Li,Al)3Al6(BO3)3Si6O18(OH)4) — mineral

Pink Tourmaline (Rubellite)

Elbaite (Tourmaline group) - Na(Li,Al)3Al6(BO3)3Si6O18(OH)4

Quartz (Milky or White Quartz) (Silicon Dioxide (SiO2)) — mineral

Quartz (Milky or White Quartz)

Silicon Dioxide (SiO2)

Larimar (Pectolite (Sodium Calcium Silicate Hydroxide) - (NaCa2(Si3O8)(OH))) — Mineral

Larimar

Pectolite (Sodium Calcium Silicate Hydroxide) - (NaCa2(Si3O8)(OH))

Fire Opal (Common/Precious in Matrix) (Hydrated Silica (SiO2·nH2O)) — mineral

Fire Opal (Common/Precious in Matrix)

Hydrated Silica (SiO2·nH2O)

Dalmatian Stone (often called Dalmatian Jasper) (Peralkaline Quartz-Feldspar Rock with Arfvedsonite (formerly believed to be Jasper)) — igneous

Dalmatian Stone (often called Dalmatian Jasper)

Peralkaline Quartz-Feldspar Rock with Arfvedsonite (formerly believed to be Jasper)

Clear Quartz (Rock Crystal) (Silicon Dioxide (SiO2)) — mineral

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Fossil Coral (Honeycomb Coral) (Favosites (extinct genus of Tabulate coral)) — sedimentary

Fossil Coral (Honeycomb Coral)

Favosites (extinct genus of Tabulate coral)

Almandine Garnet (Iron aluminum silicate (Fe3Al2(SiO4)3)) — mineral

Almandine Garnet

Iron aluminum silicate (Fe3Al2(SiO4)3)

Amethyst (Quartz) (Amethyst (SiO2 with iron impurities)) — mineral

Amethyst (Quartz)

Amethyst (SiO2 with iron impurities)

Prehnite (Prehnite, Ca2Al(AlSi3O10)(OH)2) — mineral

Prehnite

Prehnite, Ca2Al(AlSi3O10)(OH)2

Amethyst (SiO2 (Silicon Dioxide with iron impurities)) — mineral

Amethyst

SiO2 (Silicon Dioxide with iron impurities)

Chert (Iron-stained) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Iron-stained)

Microcrystalline Quartz (SiO2)

Chert (Quartz Variety) (Chert (Silicon Dioxide, SiO2)) — sedimentary

Chert (Quartz Variety)

Chert (Silicon Dioxide, SiO2)

Chert (varieties include Flint and Jasper) (Silicon Dioxide (SiO2) / Microcrystalline Quartz) — sedimentary

Chert (varieties include Flint and Jasper)

Silicon Dioxide (SiO2) / Microcrystalline Quartz