Rock Identifier

Category

Igneous Rock

Browse igneous rock specimens identified by the Rock Identifier community.

Chert / Flint (Chert (Cryptocrystalline Silica, SiO2)) — sedimentary

Chert / Flint

Chert (Cryptocrystalline Silica, SiO2)

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

Quartz (Milky/Yellowish variety)

Silicon Dioxide (SiO2)

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

Chert (Jasper)

Microcrystalline Quartz (SiO2) with iron oxide impurities

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

Fossiliferous Limestone

Biogenic Limestone (Calcium Carbonate, CaCO3)

Concretion (Septarian concretion (likely containing Calcite or Siderite)) — sedimentary

Concretion

Septarian concretion (likely containing Calcite or Siderite)

Chert Breccia (Brecciated Microcrystalline Quartz (SiO2)) — sedimentary

Chert Breccia

Brecciated Microcrystalline Quartz (SiO2)

Dyed Agate (Silicon Dioxide (SiO2)) — mineral

Dyed Agate

Silicon Dioxide (SiO2)

Coquina (Bioclastic Limestone (composed primarily of CaCO3)) — sedimentary

Coquina

Bioclastic Limestone (composed primarily of CaCO3)

Chert (Field Stone/Pebble) (Microcrystalline or cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Field Stone/Pebble)

Microcrystalline or cryptocrystalline Quartz (SiO2)

Brachiopod Fossil in Shale (Phylum Brachiopoda (often species of Order Spiriferida or Rhynchonellida)) — sedimentary

Brachiopod Fossil in Shale

Phylum Brachiopoda (often species of Order Spiriferida or Rhynchonellida)

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

Jasper (Chert)

Silicon Dioxide (SiO2)

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

Crinoid Fossil in Limestone

Crinoid (Class Crinoidea) in Fossiliferous Limestone (CaCO3)

Limonite (Iron Ore) (Goethite and related iron hydroxides (FeO(OH)·nH2O)) — mineral

Limonite (Iron Ore)

Goethite and related iron hydroxides (FeO(OH)·nH2O)

Sandstone (Arenite (predominantly Quartz Sandstone)) — sedimentary

Sandstone

Arenite (predominantly Quartz Sandstone)

Sandstone (Clastic sedimentary rock (primarily SiO2)) — sedimentary

Sandstone

Clastic sedimentary rock (primarily SiO2)

Serpentinite (Serpentine Rock) (Primarily composed of serpentine group minerals, such as antigorite, chrysotile, and lizardite. Chemical formula for serpentine minerals is (Mg,Fe)3Si2O5(OH)4.) — Metamorphic

Serpentinite (Serpentine Rock)

Primarily composed of serpentine group minerals, such as antigorite, chrysotile, and lizardite. Chemical formula for serpentine minerals is (Mg,Fe)3Si2O5(OH)4.

Rose Quartz (Silicon Dioxide (SiO2)) — mineral

Rose Quartz

Silicon Dioxide (SiO2)

Jasper with Quartz inclusions (Silicon Dioxide (SiO2) with impurities) — sedimentary

Jasper with Quartz inclusions

Silicon Dioxide (SiO2) with impurities

Jasper with Quartz Veining (Silicon Dioxide (SiO2) - Opaque cryptocrystalline variety of Quartz) — sedimentary

Jasper with Quartz Veining

Silicon Dioxide (SiO2) - Opaque cryptocrystalline variety of Quartz

Sandstone (Arenite (primarily SiO2)) — sedimentary

Sandstone

Arenite (primarily SiO2)

Sandstone (with Lichen) (Arenite (composed primarily of SiO2)) — sedimentary

Sandstone (with Lichen)

Arenite (composed primarily of SiO2)

Tiger's Eye (Pseudomorph of Quartz after Crocidolite (SiO2 with iron oxide inclusions)) — metamorphic

Tiger's Eye

Pseudomorph of Quartz after Crocidolite (SiO2 with iron oxide inclusions)

Quartzite Pebble (River Rock) (Quartzite (mainly SiO2)) — metamorphic

Quartzite Pebble (River Rock)

Quartzite (mainly SiO2)

Sandstone (with Iron Staining) (Clastic sedimentary rock (SiO2 with Fe2O3 impurities)) — sedimentary

Sandstone (with Iron Staining)

Clastic sedimentary rock (SiO2 with Fe2O3 impurities)

Sandstone (with Iron Staining) (Clastic sedimentary rock (primarily SiO2 with Fe2O3 staining)) — sedimentary

Sandstone (with Iron Staining)

Clastic sedimentary rock (primarily SiO2 with Fe2O3 staining)

Sandstone (Arenite (composed primarily of SiO2)) — sedimentary

Sandstone

Arenite (composed primarily of SiO2)

Sandstone (Quartzose Sandstone) (Clastic Terrigenous Sedimentary Rock (primarily SiO2)) — sedimentary

Sandstone (Quartzose Sandstone)

Clastic Terrigenous Sedimentary Rock (primarily SiO2)

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

Sandstone (Weathered)

Arenite (primarily SiO2)

Jasper (Yellow/Brown variety) (Silicon Dioxide (SiO2) - Microcrystalline Quartz) — sedimentary

Jasper (Yellow/Brown variety)

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Sandstone (Arenite) — sedimentary

Sandstone

Arenite

Yellow Jasper (Silicon Dioxide (SiO2) - Impure Cryptocrystalline Quartz) — sedimentary

Yellow Jasper

Silicon Dioxide (SiO2) - Impure Cryptocrystalline Quartz

Sandstone (Quartz-rich) (Arenite (composed mainly of SiO2)) — sedimentary

Sandstone (Quartz-rich)

Arenite (composed mainly of SiO2)

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

Sandstone (Quartzose)

Arenite (primarily SiO2)

Sandstone (clastic) (Clastic Sedimentary Rock (primarily composed of SiO2)) — sedimentary

Sandstone (clastic)

Clastic Sedimentary Rock (primarily composed of SiO2)

Sandstone (likely Arkose or Quartz Sandstone) (Arenite (SiO2 + varied clasts)) — sedimentary

Sandstone (likely Arkose or Quartz Sandstone)

Arenite (SiO2 + varied clasts)

Agate Geode / Nodular Chalcedony (Silicon Dioxide (SiO2) with impurities) — mineral

Agate Geode / Nodular Chalcedony

Silicon Dioxide (SiO2) with impurities

Gastropod Steinkern (Internal Mold Fossil) (Gastropoda (Class); Internal mold or 'Steinkern' composed of Calcium Carbonate (CaCO3) or Sedimentary matrix) — sedimentary

Gastropod Steinkern (Internal Mold Fossil)

Gastropoda (Class); Internal mold or 'Steinkern' composed of Calcium Carbonate (CaCO3) or Sedimentary matrix

Jasper (Silicon dioxide (SiO2) with iron oxide inclusions) — sedimentary

Jasper

Silicon dioxide (SiO2) with iron oxide inclusions

Sandstone (Clastic sedimentary rock (primarily SiO2)) — sedimentary

Sandstone

Clastic sedimentary rock (primarily SiO2)

Chert (Common Opal/Agate mixture) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (Common Opal/Agate mixture)

Microcrystalline Quartz (SiO2)

Tiger's Eye (Rough) (Pseudomorph of Quartz after Crocidolite (SiO2)) — mineral

Tiger's Eye (Rough)

Pseudomorph of Quartz after Crocidolite (SiO2)

Jasper (Jasper (Silicon Dioxide, SiO2)) — sedimentary

Jasper

Jasper (Silicon Dioxide, SiO2)