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.

Pearl (likely Freshwater or Akoya Cultured) (Aragonite / Conchiolin composite (CaCO3)) — Mineralloid (Organic gemstone)

Pearl (likely Freshwater or Akoya Cultured)

Aragonite / Conchiolin composite (CaCO3)

Mineralloid (Organic gemstone)

Turquoise (CuAl6(PO4)4(OH)8·4H2O (Hydrous phosphate of copper and aluminium)) — mineral

Turquoise

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

Caribbean Calcite (Calcium Carbonate with Argonite (CaCO3)) — mineral

Caribbean Calcite

Calcium Carbonate with Argonite (CaCO3)

Chert (Jasper) (Microcrystalline Quartz (SiO2) with iron oxide impurities) — sedimentary

Chert (Jasper)

Microcrystalline Quartz (SiO2) with iron oxide impurities

Chert (Dark Variety / Flint) (Silicon Dioxide (SiO2)) — sedimentary

Chert (Dark Variety / Flint)

Silicon Dioxide (SiO2)

Green Chert (Jasper) (Silicon Dioxide (SiO2) - Microcrystalline Quartz) — sedimentary

Green Chert (Jasper)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

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

Sodalite

Sodalite (Na8(Al6Si6O24)Cl2)

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

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Amethyst (Variety of Quartz) (Silicon Dioxide (SiO2) with iron impurities) — mineral

Amethyst (Variety of Quartz)

Silicon Dioxide (SiO2) with iron impurities

Quartz Geode in Chert/Limestone Matrix (Silicon Dioxide (SiO2) within Sedimentary Host Rock) — sedimentary

Quartz Geode in Chert/Limestone Matrix

Silicon Dioxide (SiO2) within Sedimentary Host Rock

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

Precious Opal in Matrix

Hydrated Silica (SiO2·nH2O)

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

Quartz / Milky Quartz

Silicon Dioxide (SiO2)

Amethyst (Amethyst (Silicon Dioxide, SiO2 + Fe)) — mineral

Amethyst

Amethyst (Silicon Dioxide, SiO2 + Fe)

Fossiliferous Limestone (Coquina / Shell Limestone) (Biogenic Limestone (Calcium Carbonate, CaCO3)) — sedimentary

Fossiliferous Limestone (Coquina / Shell Limestone)

Biogenic Limestone (Calcium Carbonate, CaCO3)

Aquamarine (Beryl (Be3Al2Si6O18 with trace Fe2+)) — mineral

Aquamarine

Beryl (Be3Al2Si6O18 with trace Fe2+)

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

Chert (Jasper/Agate variety)

Microcrystalline Quartz (SiO2)

Chert (Flint) (Chert (SiO2)) — sedimentary

Chert (Flint)

Chert (SiO2)

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

Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Epidote in Basalt (Epidotized Basalt (Ca2(Al2,Fe)(SiO4)(Si2O7)O(OH) in Mafic Igneous Host)) — igneous

Epidote in Basalt

Epidotized Basalt (Ca2(Al2,Fe)(SiO4)(Si2O7)O(OH) in Mafic Igneous Host)

Blue Howlite (Dyed) (Calcium Borosilicate Hydroxide (Ca2B5SiO9(OH)5)) — mineral

Blue Howlite (Dyed)

Calcium Borosilicate Hydroxide (Ca2B5SiO9(OH)5)

Opal (Hydrated Amorphous Silica (SiO2·nH2O)) — Mineral

Opal

Hydrated Amorphous Silica (SiO2·nH2O)

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

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Diamond (in Matrix) (Carbon (C)) — mineral

Diamond (in Matrix)

Carbon (C)

Carnelian (Orange Agate) (Silicon Dioxide (SiO2)) — mineral

Carnelian (Orange Agate)

Silicon Dioxide (SiO2)

Flower Jasper (Agatized Fossil Coral / Chalcedony (SiO2)) — sedimentary

Flower Jasper

Agatized Fossil Coral / Chalcedony (SiO2)

Turquoise (Turquoise (CuAl6(PO4)4(OH)8·4H2O)) — mineral

Turquoise

Turquoise (CuAl6(PO4)4(OH)8·4H2O)

Carnelian (Red Chalcedony) (Silicon Dioxide (SiO2) - variety of Chalcedony) — mineral

Carnelian (Red Chalcedony)

Silicon Dioxide (SiO2) - variety of Chalcedony

Quartz Vein in Host Rock (Silicon Dioxide (SiO2)) — mineral / metamorphic

Quartz Vein in Host Rock

Silicon Dioxide (SiO2)

mineral / metamorphic

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

Chert (Nodule)

Silicon Dioxide (SiO2)

Peridot (Olivine) ((Mg,Fe)2SiO4 (Magnesium Iron Silicate)) — mineral

Peridot (Olivine)

(Mg,Fe)2SiO4 (Magnesium Iron Silicate)

Smoky Quartz (Silicon Dioxide (SiO2)) — mineral

Smoky Quartz

Silicon Dioxide (SiO2)

Almandine Garnet in Schist (Almandine Garnet (Fe3Al2(SiO4)3) in Mica Schist) — metamorphic

Almandine Garnet in Schist

Almandine Garnet (Fe3Al2(SiO4)3) in Mica Schist

Turquoise (set in silver jewelry) (Turquoise - CuAl6(PO4)4(OH)8·4H2O (Hydrated copper and aluminum phosphate)) — mineral

Turquoise (set in silver jewelry)

Turquoise - CuAl6(PO4)4(OH)8·4H2O (Hydrated copper and aluminum phosphate)

Rough Star Sapphire (Corundum) (Al2O3 (Aluminum Oxide)) — mineral

Rough Star Sapphire (Corundum)

Al2O3 (Aluminum Oxide)

Sunstone (Oligoclase or Andesine (Plagioclase Feldspar) - (Ca, Na)((Al, Si)2Si2O8)) — mineral

Sunstone

Oligoclase or Andesine (Plagioclase Feldspar) - (Ca, Na)((Al, Si)2Si2O8)

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

Chert (Iron-stained)

Microcrystalline Quartz (SiO2)

Petrified Wood (Silicified Wood (SiO2)) — metamorphic

Petrified Wood

Silicified Wood (SiO2)

Jasper (Silicon Dioxide (SiO2) with iron oxide impurities) — sedimentary

Jasper

Silicon Dioxide (SiO2) with iron oxide impurities

Chert (specifically a weathered Chert nodule or fragment) (Chert; Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (specifically a weathered Chert nodule or fragment)

Chert; Microcrystalline or Cryptocrystalline Quartz (SiO2)

Petrified Wood (Silicified Wood (SiO2)) — metamorphic

Petrified Wood

Silicified Wood (SiO2)

Dalmatian Stone (Peralkaline Feldsphathic Igneous Rock) — igneous

Dalmatian Stone

Peralkaline Feldsphathic Igneous Rock

Chert (Chert Nodule with Chalky Cortex) (Silicon Dioxide (SiO2) - Microcrystalline Quartz) — sedimentary

Chert (Chert Nodule with Chalky Cortex)

Silicon Dioxide (SiO2) - Microcrystalline Quartz