Rock Identifier

Category

Rock

Browse rock specimens identified by the Rock Identifier community.

Granite Pebble (Granite (composed primarily of Quartz, Feldspar, and Mica)) — igneous

Granite Pebble

Granite (composed primarily of Quartz, Feldspar, and Mica)

Limestone (Calcium Carbonate (CaCO3)) — sedimentary

Limestone

Calcium Carbonate (CaCO3)

Sandstone (likely Quartzose Sandstone) (Arenite (SiO2 principal composition)) — sedimentary

Sandstone (likely Quartzose Sandstone)

Arenite (SiO2 principal composition)

Quartz Vein in Host Rock (Gneiss/Schist) (Silicon Dioxide (SiO2) within a metamorphic matrix) — metamorphic

Quartz Vein in Host Rock (Gneiss/Schist)

Silicon Dioxide (SiO2) within a metamorphic matrix

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

Basalt

Basalt (Aphanitic Mafic Igneous Rock)

River Pebble (Likely Quartzite or Gneiss) (Metamorphosed Silicate Rock (primarily SiO2)) — metamorphic

River Pebble (Likely Quartzite or Gneiss)

Metamorphosed Silicate Rock (primarily SiO2)

Sandstone (with potential trace fossils) (Clastic sedimentary rock (primarily SiO2)) — sedimentary

Sandstone (with potential trace fossils)

Clastic sedimentary rock (primarily SiO2)

Sandstone (with Iron Staining) (Clastic Sedimentary Rock (primarily SiO2)) — sedimentary

Sandstone (with Iron Staining)

Clastic Sedimentary Rock (primarily SiO2)

Chert Conglomerate (or Breccia) (Sedimentary Clastic Rock (variety: Ferruginous Chert Breccia)) — sedimentary

Chert Conglomerate (or Breccia)

Sedimentary Clastic Rock (variety: Ferruginous Chert Breccia)

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

Carnelian (Orange Agate)

Silicon Dioxide (SiO2)

Gneiss (Gneiss (High-grade Metamorphic Rock)) — metamorphic

Gneiss

Gneiss (High-grade Metamorphic Rock)

Basalt with Quartz/Calcite Vein (Basalt (Mafic Volcanic Rock with secondary mineralization)) — igneous

Basalt with Quartz/Calcite Vein

Basalt (Mafic Volcanic Rock with secondary mineralization)

Microcrystalline Limestone Pebble (Carbonate sedimentary rock (Calcium Carbonate, CaCO3)) — sedimentary

Microcrystalline Limestone Pebble

Carbonate sedimentary rock (Calcium Carbonate, CaCO3)

Sandstone (likely Ferruginous) (Sandstone (SiO2 with iron oxides)) — sedimentary

Sandstone (likely Ferruginous)

Sandstone (SiO2 with iron oxides)

River Cobble (likely Quartzite or Limestone) (SiO2 (Quartzite dominant) or CaCO3 (Limestone dominant)) — metamorphic or sedimentary

River Cobble (likely Quartzite or Limestone)

SiO2 (Quartzite dominant) or CaCO3 (Limestone dominant)

metamorphic or sedimentary

Granodiorite (Phaneritic intrusive igneous rock (Granodiorite)) — igneous

Granodiorite

Phaneritic intrusive igneous rock (Granodiorite)

Sandstone Geode (Unbroken) (Siliciclastic sedimentary rock (primarily Quartz)) — sedimentary

Sandstone Geode (Unbroken)

Siliciclastic sedimentary rock (primarily Quartz)

Sandstone (Weathered Cobble) (Clastic Sedimentary Rock (primarily SiO2)) — sedimentary

Sandstone (Weathered Cobble)

Clastic Sedimentary Rock (primarily SiO2)

Sandstone (with potential trace fossils) (Clastic sedimentary rock (primarily SiO2)) — sedimentary

Sandstone (with potential trace fossils)

Clastic sedimentary rock (primarily SiO2)

Dalmatian Stone (Dalmatian Stone (a fine-grained igneous rock, often misidentified as Dalmatian Jasper)) — igneous

Dalmatian Stone

Dalmatian Stone (a fine-grained igneous rock, often misidentified as Dalmatian Jasper)

Basalt (Mafic volcanic rock (primarily Plagioclase and Pyroxene)) — igneous

Basalt

Mafic volcanic rock (primarily Plagioclase and Pyroxene)

Granite (Granite (Phaneritic Quartz-Feldspar Plutonic Rock)) — igneous

Granite

Granite (Phaneritic Quartz-Feldspar Plutonic Rock)

Quartzite (Quartzite (SiO2)) — metamorphic

Quartzite

Quartzite (SiO2)

Quartzite (River Cobble) (Metamorphic Rock (composed predominantly of SiO2)) — metamorphic

Quartzite (River Cobble)

Metamorphic Rock (composed predominantly of SiO2)

Dalmatian Stone (Dalmatian Jasper (a misnomer for an Aplite with Arfvedsonite spots)) — igneous

Dalmatian Stone

Dalmatian Jasper (a misnomer for an Aplite with Arfvedsonite spots)

Granite (Granite (Mainly Quartz, Feldspar, and Mica)) — igneous

Granite

Granite (Mainly Quartz, Feldspar, and Mica)

Dalmatian Stone (Dalmatian Stone (a peralkaline igneous rock consisting of Feldspar, Quartz, and Arfvedsonite)) — igneous

Dalmatian Stone

Dalmatian Stone (a peralkaline igneous rock consisting of Feldspar, Quartz, and Arfvedsonite)

Sandstone Pebble (Arenite (primarily SiO2)) — sedimentary

Sandstone Pebble

Arenite (primarily SiO2)

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

Chert (containing Quartz)

Microcrystalline Silica (SiO2)

Sandstone (Arenite (primarily SiO2)) — sedimentary

Sandstone

Arenite (primarily SiO2)

Ironstone Concretion / Goethite-Hematite Nodule (Goethite/Hematite (α-FeO(OH) / Fe2O3)) — sedimentary

Ironstone Concretion / Goethite-Hematite Nodule

Goethite/Hematite (α-FeO(OH) / Fe2O3)

Blue Lace Agate (Cryptocrystalline Quartz (SiO2) with trace minerals) — sedimentary

Blue Lace Agate

Cryptocrystalline Quartz (SiO2) with trace minerals

Basalt (Mafic Volcanic Rock (Primarily Plagioclase Feldspar and Pyroxene)) — igneous

Basalt

Mafic Volcanic Rock (Primarily Plagioclase Feldspar and Pyroxene)

Sandstone (Arenite) — sedimentary

Sandstone

Arenite

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

Sandstone

Arenite (composed primarily of Quartz, SiO2)

Sandstone (Quartzite-rich Cobble) (Clastic sedimentary rock (primarily SiO2)) — sedimentary

Sandstone (Quartzite-rich Cobble)

Clastic sedimentary rock (primarily SiO2)

Conglomerate (Clastic sedimentary rock (Polymictic Conglomerate)) — sedimentary

Conglomerate

Clastic sedimentary rock (Polymictic Conglomerate)

Sandstone (Ferruginous) (Arenite (Fe-rich)) — sedimentary

Sandstone (Ferruginous)

Arenite (Fe-rich)

Quartzite (Quartzite (primarily SiO2)) — metamorphic

Quartzite

Quartzite (primarily SiO2)

Basalt (Basalt (Mafic Extrusive Igneous Rock)) — igneous

Basalt

Basalt (Mafic Extrusive Igneous Rock)

Pumice (Vesicular volcanic glass (primarily SiO2)) — igneous

Pumice

Vesicular volcanic glass (primarily SiO2)

Amygdaloidal Basalt (Amygdaloidal Basalt (Mafic Volcanic Rock)) — igneous

Amygdaloidal Basalt

Amygdaloidal Basalt (Mafic Volcanic Rock)