Rock Identifier

Category

Organic Gemstone (Not A Rock)

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

Fossiliferous Limestone (Biogenic Limestone (Calcium Carbonate, CaCO3)) — sedimentary

Fossiliferous Limestone

Biogenic Limestone (Calcium Carbonate, CaCO3)

Concrete Rubble with Aggregate (Hardened Portland Cement Paste with Coarse Aggregate) — Anthropogenic (Man-made)

Concrete Rubble with Aggregate

Hardened Portland Cement Paste with Coarse Aggregate

Anthropogenic (Man-made)

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

Garnet

Almandine (Fe3Al2(SiO4)3)

Mudstone (Lutylite (group of fine-grained sedimentary rocks)) — sedimentary

Mudstone

Lutylite (group of fine-grained sedimentary rocks)

Sandstone (Arenite (SiO2 based)) — sedimentary

Sandstone

Arenite (SiO2 based)

Basalt with Quartz Veins (Basalt (composition: SiO2, MgO, FeO, Al2O3, CaO)) — igneous

Basalt with Quartz Veins

Basalt (composition: SiO2, MgO, FeO, Al2O3, CaO)

Basalt (Basalt (Mafic volcanic rock)) — igneous

Basalt

Basalt (Mafic volcanic rock)

Fossiliferous Shale (with Vertebrate Bones) (Laminated Mudstone containing Fossilized Bone (Apatite)) — sedimentary

Fossiliferous Shale (with Vertebrate Bones)

Laminated Mudstone containing Fossilized Bone (Apatite)

Asphalt (Road Aggregate) (Asphalt concrete / Bituminous mixture) — anthropogenic sedimentary (technolith)

Asphalt (Road Aggregate)

Asphalt concrete / Bituminous mixture

anthropogenic sedimentary (technolith)

Quartz Vein in Gneiss or Basalt (Milky Quartz (SiO2) within Metamorphic Host Rock) — Metamorphic or Igneous with Mineral Inclusion

Quartz Vein in Gneiss or Basalt

Milky Quartz (SiO2) within Metamorphic Host Rock

Metamorphic or Igneous with Mineral Inclusion

Limestone (Calcium Carbonate (CaCO3)) — sedimentary

Limestone

Calcium Carbonate (CaCO3)

Rough Amethyst (Silicon Dioxide (SiO2) with Iron impurities) — mineral

Rough Amethyst

Silicon Dioxide (SiO2) with Iron impurities

Blue Moss Agate (Silicon Dioxide (SiO2) with mineral inclusions) — sedimentary

Blue Moss Agate

Silicon Dioxide (SiO2) with mineral inclusions

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

Chert (Quartz)

Microcrystalline Silica (SiO2)

Ruby in Zoisite with Hornblende (Anyolite (Ruby: Al2O3, Zoisite: Ca2Al3(SiO4)3(OH))) — metamorphic

Ruby in Zoisite with Hornblende

Anyolite (Ruby: Al2O3, Zoisite: Ca2Al3(SiO4)3(OH))

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

Sandstone (Quartzose)

Arenite (primarily SiO2)

Gneiss (High-grade regional metamorphic rock (Foliated)) — metamorphic

Gneiss

High-grade regional metamorphic rock (Foliated)

Garnet Schist (Almandine-Garnet Mica Schist) — metamorphic

Garnet Schist

Almandine-Garnet Mica Schist

Sandstone (Ferruginous/Red Sandstone) (Clastic sedimentary rock (primarily SiO2 with Fe2O3)) — sedimentary

Sandstone (Ferruginous/Red Sandstone)

Clastic sedimentary rock (primarily SiO2 with Fe2O3)

Jasper (River pebble) (Jasper / Silicon Dioxide (SiO2)) — sedimentary

Jasper (River pebble)

Jasper / Silicon Dioxide (SiO2)

Quartz Vein in Host Rock (Silicon Dioxide (SiO2) within Matrix) — igneous/metamorphic

Quartz Vein in Host Rock

Silicon Dioxide (SiO2) within Matrix

igneous/metamorphic

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

Amethyst (Purple Quartz)

Silicon Dioxide (SiO2) with iron impurities

Chert (Yellow Jasper variant) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Yellow Jasper variant)

Microcrystalline Quartz (SiO2)

Chert (Lightly weathered variety) (Silicon Dioxide (SiO2) - Microcrystalline Quartz) — sedimentary

Chert (Lightly weathered variety)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Carnelian Agate (Silicon Dioxide (SiO2)) — mineral

Carnelian Agate

Silicon Dioxide (SiO2)

Serpentine (New Jade) (Antigorite, Lizardite, and Chrysotile (Mg3Si2O5(OH)4)) — metamorphic

Serpentine (New Jade)

Antigorite, Lizardite, and Chrysotile (Mg3Si2O5(OH)4)

Dendritic Jasper (Silicon Dioxide (SiO2) with Manganese/Iron oxide inclusions) — sedimentary

Dendritic Jasper

Silicon Dioxide (SiO2) with Manganese/Iron oxide inclusions

Carnelian (Carnelian (SiO2 variant)) — mineral

Carnelian

Carnelian (SiO2 variant)

Petrified Wood (Silicified wood, primarily composed of Quartz (SiO2)) — Mineral, often found in sedimentary deposits

Petrified Wood

Silicified wood, primarily composed of Quartz (SiO2)

Mineral, often found in sedimentary deposits

Banded Chert (River Cobble) (Microcrystalline Quartz (SiO2)) — sedimentary

Banded Chert (River Cobble)

Microcrystalline Quartz (SiO2)

Red Chalcedony (likely dyed) (Chalcedony (a variety of Quartz), SiO2) — Mineral (Cryptocrystalline Quartz)

Red Chalcedony (likely dyed)

Chalcedony (a variety of Quartz), SiO2

Mineral (Cryptocrystalline Quartz)

Magnetite / Iron Ore (Magnetite (Fe3O4)) — mineral

Magnetite / Iron Ore

Magnetite (Fe3O4)

Amethyst (Tumbled Chips) (Amethyst (Silicon Dioxide with Iron impurities, SiO2)) — mineral

Amethyst (Tumbled Chips)

Amethyst (Silicon Dioxide with Iron impurities, SiO2)

Chert (with Quartz Veining) (Chert (formula: SiO2)) — sedimentary

Chert (with Quartz Veining)

Chert (formula: SiO2)

River Rock (Greywacke/Sandstone) (Lithic Wacke) — sedimentary

River Rock (Greywacke/Sandstone)

Lithic Wacke

Quartzite (with Iron Staining) (Metamorphosed Quartz Sandstone (SiO2)) — metamorphic

Quartzite (with Iron Staining)

Metamorphosed Quartz Sandstone (SiO2)

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

Amethyst

Silicon Dioxide (SiO2) with iron impurities

Limonite (Ironstone) (Limonite (mixture of hydrated iron oxides, primarily Goethite α-FeO(OH))) — mineral

Limonite (Ironstone)

Limonite (mixture of hydrated iron oxides, primarily Goethite α-FeO(OH))

Limonite (Iron Ore) (Limonite (̑FeO(OH)·nH₂O)) — sedimentary

Limonite (Iron Ore)

Limonite (̑FeO(OH)·nH₂O)

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

Chert (Iron-stained)

Microcrystalline or cryptocrystalline Quartz (SiO2)

Quartzite (River Stone) (Quartzite) — metamorphic

Quartzite (River Stone)

Quartzite

Hematite Beads (Hematite (Fe2O3)) — Mineral

Hematite Beads

Hematite (Fe2O3)