Rock Identifier

Category

Organic Structure (Not A Rock)

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

Conglomerate (Conglomerate (clastic sedimentary rock type)) — sedimentary

Conglomerate

Conglomerate (clastic sedimentary rock type)

Quartzite (Quartzite (SiO2)) — metamorphic

Quartzite

Quartzite (SiO2)

Mica Schist (Mica Schist) — metamorphic

Mica Schist

Mica Schist

Coquina (Bioclastic Limestone) — sedimentary

Coquina

Bioclastic Limestone

Granite (Phaneritic Plutonic Igneous Rock (composed of Quartz, Alkali Feldspar, and Plagioclase)) — igneous

Granite

Phaneritic Plutonic Igneous Rock (composed of Quartz, Alkali Feldspar, and Plagioclase)

Granite Pebble (Granite (Phaneritic intrusive igneous rock comprising Quartz, Feldspar, and Mica)) — igneous

Granite Pebble

Granite (Phaneritic intrusive igneous rock comprising Quartz, Feldspar, and Mica)

Quartz (Iron-stained or Rose variant) (Silicon Dioxide (SiO2)) — mineral

Quartz (Iron-stained or Rose variant)

Silicon Dioxide (SiO2)

Serpentinite (Serpentinite (composed primarily of Serpentine group minerals: (Mg,Fe)3Si2O5(OH)4)) — metamorphic

Serpentinite

Serpentinite (composed primarily of Serpentine group minerals: (Mg,Fe)3Si2O5(OH)4)

Unakite (Unakite (Epidotized Granite)) — metamorphic

Unakite

Unakite (Epidotized Granite)

Quartz Vein in Pelite (Metamorphic Rock) (Hydrothermal Quartz Veining in Metasedimentary Rock (SiO2)) — metamorphic

Quartz Vein in Pelite (Metamorphic Rock)

Hydrothermal Quartz Veining in Metasedimentary Rock (SiO2)

Quartz (Iron-stained) (Silicon Dioxide (SiO2)) — mineral

Quartz (Iron-stained)

Silicon Dioxide (SiO2)

Basalt with Plagioclase Phenocrysts (Porphyritic Basalt) — igneous

Basalt with Plagioclase Phenocrysts

Porphyritic Basalt

Granatic Pegmatite (Pegmatitic Granite) — igneous

Granatic Pegmatite

Pegmatitic Granite

Quartz / Common Opal (Silicon Dioxide (SiO2)) — mineral

Quartz / Common Opal

Silicon Dioxide (SiO2)

Granodiorite (Granodiorite (Intermediate intrusive igneous rock)) — igneous

Granodiorite

Granodiorite (Intermediate intrusive igneous rock)

Granite (Granite (Silicic Plutonic Rock)) — igneous

Granite

Granite (Silicic Plutonic Rock)

Schist (Schist (Crystalline metamorphic rock)) — metamorphic

Schist

Schist (Crystalline metamorphic rock)

Fossiliferous Limestone (Chertified Limestone) (Calcium Carbonate (CaCO3) often replaced by Microcrystalline Silica (SiO2)) — sedimentary

Fossiliferous Limestone (Chertified Limestone)

Calcium Carbonate (CaCO3) often replaced by Microcrystalline Silica (SiO2)

Chert (Chalk-associated Flint) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (Chalk-associated Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Marble (Marble (metamorphosed limestone or dolostone), primarily composed of calcite (CaCO3) or dolomite (CaMg(CO3)2)) — metamorphic

Marble

Marble (metamorphosed limestone or dolostone), primarily composed of calcite (CaCO3) or dolomite (CaMg(CO3)2)

Mookaite Jasper (Silicified Radiolarite (Silicon Dioxide: SiO2)) — sedimentary

Mookaite Jasper

Silicified Radiolarite (Silicon Dioxide: SiO2)

Chert (or Flint) (Silicon dioxide (SiO2)) — sedimentary

Chert (or Flint)

Silicon dioxide (SiO2)

Mica Schist (Mica Schist (KAl2(AlSi3O10)(OH)2 / K(Mg,Fe)3AlSi3O10(OH)2)) — metamorphic

Mica Schist

Mica Schist (KAl2(AlSi3O10)(OH)2 / K(Mg,Fe)3AlSi3O10(OH)2)

Chert (specifically Flint or Dark Chalcedony) (Silicon Dioxide (SiO2)) — sedimentary

Chert (specifically Flint or Dark Chalcedony)

Silicon Dioxide (SiO2)

Pumice (Highly vesicular volcanic glass (unnamed scientific variant: Rhyolitic/Andesitic Pumice)) — igneous

Pumice

Highly vesicular volcanic glass (unnamed scientific variant: Rhyolitic/Andesitic Pumice)

Quartzite Pebbler (Quartzite (SiO2)) — metamorphic

Quartzite Pebbler

Quartzite (SiO2)

River Cobble (Quartzite) (Meta-orthoquartzite) — metamorphic

River Cobble (Quartzite)

Meta-orthoquartzite

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

Tiger's Eye

Pseudomorph of Quartz after Crocidolite (SiO2)

Obsidian (Volcanic Glass (70-75% SiO2)) — igneous

Obsidian

Volcanic Glass (70-75% SiO2)

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

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

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

Amethyst

Amethyst (Silicon Dioxide - SiO2)

Quartz Pebble (Silicon Dioxide (SiO2)) — mineral

Quartz Pebble

Silicon Dioxide (SiO2)

River Pebble (Likely Quartzite or Chert) (Quartzite (primarily SiO2)) — metamorphic

River Pebble (Likely Quartzite or Chert)

Quartzite (primarily SiO2)

Snowflake Obsidian (Volcanic glass with Spherulite inclusions (SiO2)) — igneous

Snowflake Obsidian

Volcanic glass with Spherulite inclusions (SiO2)

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

Sandstone

Arenite (often composed of Quartz, SiO2)

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

Sandstone (with Iron Staining)

Clastic sedimentary rock (primarily SiO2)

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

Sandstone

Arenite (composed primarily of SiO2)

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

Tiger's Eye

Pseudomorph of Quartz after Crocidolite (SiO2 with iron inclusions)

Jasper (Iron-stained Quartzite/Chert) (Silicon Dioxide (SiO2) with iron oxide inclusions) — sedimentary

Jasper (Iron-stained Quartzite/Chert)

Silicon Dioxide (SiO2) with iron oxide inclusions

Red Jasper (Silicon Dioxide (SiO2) with iron oxide inclusions) — sedimentary

Red Jasper

Silicon Dioxide (SiO2) with iron oxide inclusions

Jasper (likely Brecciated or Multi-colored) (Jasper (SiO2)) — sedimentary

Jasper (likely Brecciated or Multi-colored)

Jasper (SiO2)

Granite Gneiss (Gneiss (High-grade regional metamorphic rock)) — Metamorphic

Granite Gneiss

Gneiss (High-grade regional metamorphic rock)