Rock Identifier

Category

Organic Structure (Not A Rock)

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

Petrified Wood (Silicified Wood (primarily SiO₂)) — sedimentary

Petrified Wood

Silicified Wood (primarily SiO₂)

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

Chert (Jasper variety)

Silicon Dioxide (SiO2)

Granite (Granite) — Igneous

Granite

Granite

Druzy Quartz on Matrix (likely Limestone or Sandstone) (Silicon Dioxide (SiO2) with various trace impurities) — Mineral on Sedimentary Rock

Druzy Quartz on Matrix (likely Limestone or Sandstone)

Silicon Dioxide (SiO2) with various trace impurities

Mineral on Sedimentary Rock

Banded Slate or Siltstone with Quartz/Calcite Veins (Protolith-derived Siltstone or Slate (varies based on degree of metamorphism)) — metamorphic

Banded Slate or Siltstone with Quartz/Calcite Veins

Protolith-derived Siltstone or Slate (varies based on degree of metamorphism)

Unakite (Epidote-Feldspar rock) — Metamorphic Rock

Unakite

Epidote-Feldspar rock

Metamorphic Rock

River Pebble (Gravel) (Clastic sedimentary rock (likely Siltstone or Mudstone pebble; SiO2 with various impurities)) — sedimentary

River Pebble (Gravel)

Clastic sedimentary rock (likely Siltstone or Mudstone pebble; SiO2 with various impurities)

Pink Opal (Hydrated Silica (SiO2·nH2O) with Palygorskite inclusions) — Mineraloid

Pink Opal

Hydrated Silica (SiO2·nH2O) with Palygorskite inclusions

Diorite (Diorite (Intermediate intrusive igneous rock)) — igneous

Diorite

Diorite (Intermediate intrusive igneous rock)

Granodiorite (Phaneritic-textured Intrusive Granodiorite) — igneous

Granodiorite

Phaneritic-textured Intrusive Granodiorite

Vesicular Basalt with Epidote (Vesicular Basalt (Mg, Fe)2SiO4 with Epidote (Ca2(Al2,Fe)(SiO4)(Si2O7)O(OH))) — igneous

Vesicular Basalt with Epidote

Vesicular Basalt (Mg, Fe)2SiO4 with Epidote (Ca2(Al2,Fe)(SiO4)(Si2O7)O(OH))

Basalt (Basalt) — igneous

Basalt

Basalt

Amber with Inclusion (Succiniferous fossil resin (C10H16O)) — mineraloid

Amber with Inclusion

Succiniferous fossil resin (C10H16O)

Granodiorite with Quartz Veining (Granodiorite (containing Plagioclase Feldspar, Quartz, and Biotite/Hornblende) with Quartz (SiO2) veins) — igneous

Granodiorite with Quartz Veining

Granodiorite (containing Plagioclase Feldspar, Quartz, and Biotite/Hornblende) with Quartz (SiO2) veins

Smoky Quartz (Silicon Dioxide (SiO2)) — mineral

Smoky Quartz

Silicon Dioxide (SiO2)

Basalt with Iron Oxidation (Lattice/Veined) (Mafic Volcanic Rock (principally Plagioclase and Pyroxene)) — igneous

Basalt with Iron Oxidation (Lattice/Veined)

Mafic Volcanic Rock (principally Plagioclase and Pyroxene)

Druzy Quartz on Chalcedony Matrix (Silicon Dioxide (SiO2)) — mineral

Druzy Quartz on Chalcedony Matrix

Silicon Dioxide (SiO2)

Amber (Succinite (with a generalized formula of C10H16O)) — mineral

Amber

Succinite (with a generalized formula of C10H16O)

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

Sandstone

Clastic sedimentary rock (primarily SiO2)

Asphalt Chunk (with aggregate) (Bituminous concrete / Anthropogenic conglomerate) — sedimentary (anthropogenic/man-made conglomerate)

Asphalt Chunk (with aggregate)

Bituminous concrete / Anthropogenic conglomerate

sedimentary (anthropogenic/man-made conglomerate)

Amber (Rough) (Amber (Fossilized Tree Resin, succinite)) — mineral

Amber (Rough)

Amber (Fossilized Tree Resin, succinite)

Vesicular Basalt (Scoria) (Vesicular Basalt) — igneous

Vesicular Basalt (Scoria)

Vesicular Basalt

Agate (Common Chalcedony) (Silicon Dioxide (SiO2)) — mineral

Agate (Common Chalcedony)

Silicon Dioxide (SiO2)

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

Sandstone (Quartzose)

Arenite (primarily SiO2)

Basalt with Quartz/Quartzite Veins (Aphanitic Mafic Volcanic Rock with Siliceous Infillings) — igneous

Basalt with Quartz/Quartzite Veins

Aphanitic Mafic Volcanic Rock with Siliceous Infillings

Granite Pebble (Granite (Phaneritic intrusive igneous rock)) — igneous

Granite Pebble

Granite (Phaneritic intrusive igneous rock)

Moss Agate (Cryptocrystalline Quartz (SiO2 with Manganese or Iron Oxide inclusions)) — mineral

Moss Agate

Cryptocrystalline Quartz (SiO2 with Manganese or Iron Oxide inclusions)

Chert (specifically Blue Chert or Flint) (Microcrystalline or Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert (specifically Blue Chert or Flint)

Microcrystalline or Cryptocrystalline Quartz (SiO2)

Basalt (Mafic volcanic rock (primarily plagioclase, pyroxene, and olivine)) — Igneous

Basalt

Mafic volcanic rock (primarily plagioclase, pyroxene, and olivine)

Conglomerate (Conglomerate (Detrital Sedimentary Rock)) — sedimentary

Conglomerate

Conglomerate (Detrital Sedimentary Rock)

Amber (Succinate (Fossilized Tree Resin)) — mineraloid

Amber

Succinate (Fossilized Tree Resin)

Granite (Granite) — Igneous

Granite

Granite

Shale (Fissile Siliciclastic Sedimentary Rock) — sedimentary

Shale

Fissile Siliciclastic Sedimentary Rock

Basalt (Afanitic Mafic Basalt) — igneous

Basalt

Afanitic Mafic Basalt

Basalt with Plagioclase Phenocrysts (Porphyritic Basalt) — igneous

Basalt with Plagioclase Phenocrysts

Porphyritic Basalt

Chert (Arrowhead) (Chert (primarily Microcrystalline Silica, SiO2)) — sedimentary

Chert (Arrowhead)

Chert (primarily Microcrystalline Silica, SiO2)

Quartz Vein Rock (Quartz (Silicon Dioxide, SiO2)) — igneous

Quartz Vein Rock

Quartz (Silicon Dioxide, SiO2)

Chert (often colloquially referred to as Flint) (Chert (Cryptocrystalline Quartz, SiO2)) — sedimentary

Chert (often colloquially referred to as Flint)

Chert (Cryptocrystalline Quartz, SiO2)

Chert / Flint (Cryptocrystalline Quartz (SiO2)) — sedimentary

Chert / Flint

Cryptocrystalline Quartz (SiO2)

Chert (vuggy variety) (Microcrystalline silica (SiO2)) — sedimentary

Chert (vuggy variety)

Microcrystalline silica (SiO2)

Chert (Nodule) (Chert (primarily Microcrystalline Quartz - SiO2)) — sedimentary

Chert (Nodule)

Chert (primarily Microcrystalline Quartz - SiO2)

Chert (specifically River Stone / Jasper variety) (Microcrystalline Quartz (SiO2)) — sedimentary

Chert (specifically River Stone / Jasper variety)

Microcrystalline Quartz (SiO2)