Rock Identifier

Category

Organic Gemstone (Not A Rock)

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

Banded Agate (specifically Sardonyx or Carnelian Agate) (Silicon Dioxide (SiO2) - Cryptocrystalline Quartz) — mineral

Banded Agate (specifically Sardonyx or Carnelian Agate)

Silicon Dioxide (SiO2) - Cryptocrystalline Quartz

Granite (Granite (Felsic Plutonic Rock)) — igneous

Granite

Granite (Felsic Plutonic Rock)

Quartzite (Quartzite (SiO2)) — metamorphic

Quartzite

Quartzite (SiO2)

Quartzite Pebble (Meta-quartzite) — metamorphic

Quartzite Pebble

Meta-quartzite

ABS Plastic (Acrylonitrile Butadiene Styrene) ((C8H8)x·(C4H6)y·(C3H3N)z) — Synthetic Polymer (Synthetic Material)

ABS Plastic (Acrylonitrile Butadiene Styrene)

(C8H8)x·(C4H6)y·(C3H3N)z

Synthetic Polymer (Synthetic Material)

Chert (Limestone-based) (Silicon Dioxide (SiO2)) — sedimentary

Chert (Limestone-based)

Silicon Dioxide (SiO2)

Dalmatian Stone (Dalmatian Jasper) (Peralkaline Quartz-Feldspar Porphyry with Arfvedsonite) — igneous

Dalmatian Stone (Dalmatian Jasper)

Peralkaline Quartz-Feldspar Porphyry with Arfvedsonite

Dalmation Stone (often called Dalmatian Jasper) (Antiperthite-rich Microgranite) — igneous

Dalmation Stone (often called Dalmatian Jasper)

Antiperthite-rich Microgranite

Dalmatian Stone (often misnamed Dalmatian Jasper) (Aplite (with hornblende/arfvedsonite inclusions)) — igneous

Dalmatian Stone (often misnamed Dalmatian Jasper)

Aplite (with hornblende/arfvedsonite inclusions)

Dalmation Jasper (Dalmation Stone) (Perthitic feldspar-quartz-amphibole rock) — igneous

Dalmation Jasper (Dalmation Stone)

Perthitic feldspar-quartz-amphibole rock

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

Carnelian

Carnelian (Silicon Dioxide - SiO2)

Spiny Oyster Shell (Spondylus varians (Biogenic Calcium Carbonate)) — mineral

Spiny Oyster Shell

Spondylus varians (Biogenic Calcium Carbonate)

Polished Jasper (Mushroom Carving) (Silicon Dioxide (SiO2) - Microcrystalline Quartz) — sedimentary

Polished Jasper (Mushroom Carving)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Brown Agate (Silicon Dioxide (SiO2)) — mineral

Brown Agate

Silicon Dioxide (SiO2)

Yellow Jasper (Silicon Dioxide (SiO2) with iron inclusions) — sedimentary

Yellow Jasper

Silicon Dioxide (SiO2) with iron inclusions

Pyrite (Iron Sulfide (FeS2)) — mineral

Pyrite

Iron Sulfide (FeS2)

Blue Apatite (Apatite (Calcium Phosphate) - Ca5(PO4)3(F,Cl,OH)) — mineral

Blue Apatite

Apatite (Calcium Phosphate) - Ca5(PO4)3(F,Cl,OH)

River Rock (Greywacke/Siltstone) (Siltstone / Argillaceous Greywacke) — sedimentary

River Rock (Greywacke/Siltstone)

Siltstone / Argillaceous Greywacke

Crinaudite / Fossilized Crinoid Stem (Crinoid (Echinodermata) in a Calcitic/Siliceous Matrix) — sedimentary

Crinaudite / Fossilized Crinoid Stem

Crinoid (Echinodermata) in a Calcitic/Siliceous Matrix

Granite (Granite (Silicic Plutonic Rock)) — igneous

Granite

Granite (Silicic Plutonic Rock)

Dalmatian Stone (Peralkaline rhyolite) — igneous

Dalmatian Stone

Peralkaline rhyolite

Ruby in Zoisite (Anyolite) (Anyolite (Combination of Corundum and Zoisite)) — metamorphic

Ruby in Zoisite (Anyolite)

Anyolite (Combination of Corundum and Zoisite)

Banded Iron Formation (BIF) / Tiger Iron (Ferruginous Chert (primarily Quartz [SiO2] and Hematite/Magnetite [Fe2O3/Fe3O4])) — metamorphic

Banded Iron Formation (BIF) / Tiger Iron

Ferruginous Chert (primarily Quartz [SiO2] and Hematite/Magnetite [Fe2O3/Fe3O4])

Sandstone (Clastic Sedimentary Rock (composed of SiO2 grains)) — sedimentary

Sandstone

Clastic Sedimentary Rock (composed of SiO2 grains)

Granite (Granitoid) — igneous

Granite

Granitoid

Sandstone (likely Arkosic or Quartzose) (Arenite (SiO2 based with mineral inclusions)) — sedimentary

Sandstone (likely Arkosic or Quartzose)

Arenite (SiO2 based with mineral inclusions)

Quartzite (Quartzite (SiO2)) — metamorphic

Quartzite

Quartzite (SiO2)

Chert (Jasper variety) (Silicon Dioxide (SiO2)) — sedimentary

Chert (Jasper variety)

Silicon Dioxide (SiO2)

Red Jasper (Silicon Dioxide (SiO2) with iron oxide impurities) — mineral

Red Jasper

Silicon Dioxide (SiO2) with iron oxide impurities

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

Chert (Quartz Variety)

Chert (Silicon Dioxide, SiO2)

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

Amethyst

Silicon Dioxide with iron impurities (SiO2)

Chalcedony in Limestone Host Rock (Silicon Dioxide (SiO2) within Calcium Carbonate (CaCO3)) — Mineral within Sedimentary Rock

Chalcedony in Limestone Host Rock

Silicon Dioxide (SiO2) within Calcium Carbonate (CaCO3)

Mineral within Sedimentary Rock

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

Amethyst

Silicon Dioxide (SiO2) with iron impurities

Bloodstone (Heliotrope (cryptocrystalline Quartz, SiO2 with inclusions of Hematite)) — sedimentary

Bloodstone

Heliotrope (cryptocrystalline Quartz, SiO2 with inclusions of Hematite)

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

Clear Quartz Crystal

Silicon Dioxide (SiO2)

Mica (Muscovite) (Potassium aluminum silicate - KAl2(AlSi3O10)(OH)2) — mineral

Mica (Muscovite)

Potassium aluminum silicate - KAl2(AlSi3O10)(OH)2

Oolitic Chert (Oolitic Microcrystalline Quartz (SiO2)) — sedimentary

Oolitic Chert

Oolitic Microcrystalline Quartz (SiO2)

Crushed Rock (Basalt) (Basalt (Aphanitic Mafic Igneous Rock)) — Igneous

Crushed Rock (Basalt)

Basalt (Aphanitic Mafic Igneous Rock)

Quartz Geode (with Calcite influence) (Silicon Dioxide (SiO2) with possible Calcium Carbonate (CaCO3)) — mineral

Quartz Geode (with Calcite influence)

Silicon Dioxide (SiO2) with possible Calcium Carbonate (CaCO3)

Jasper with Epidote (Silicon Dioxide (SiO2) with Calcium Aluminum Iron Sorosilicate [Ca2Al2Fe3+Si3O12(OH)]) — sedimentary/metamorphic

Jasper with Epidote

Silicon Dioxide (SiO2) with Calcium Aluminum Iron Sorosilicate [Ca2Al2Fe3+Si3O12(OH)]

sedimentary/metamorphic

Banded Agate (Cryptocrystalline variety of Quartz (SiO2)) — mineral

Banded Agate

Cryptocrystalline variety of Quartz (SiO2)

Red Jasper (Silicon Dioxide (SiO2) with Iron Oxide (Fe2O3) inclusions) — sedimentary

Red Jasper

Silicon Dioxide (SiO2) with Iron Oxide (Fe2O3) inclusions