Rock Identifier

Category

Igneous Rock (Volcanic Glass)

Browse igneous rock (volcanic glass) specimens identified by the Rock Identifier community.

Black Obsidian (Volcanic Glass (predominantly SiO2)) — igneous

Black Obsidian

Volcanic Glass (predominantly SiO2)

igneous
Apache Tear (Hydrated Obsidian (Volcanic Glass)) — Igneous

Apache Tear

Hydrated Obsidian (Volcanic Glass)

Igneous
Obsidian (Volcanic Glass (predominantly SiO2)) — igneous

Obsidian

Volcanic Glass (predominantly SiO2)

igneous
Obsidian (Volcanic Glass (SiO2 + impurities)) — igneous

Obsidian

Volcanic Glass (SiO2 + impurities)

igneous
Quartz / Common Agate (Silicon Dioxide (SiO2)) — mineral

Quartz / Common Agate

Silicon Dioxide (SiO2)

mineral
Obsidian (Volcanic Glass (Amorphous Silica)) — igneous

Obsidian

Volcanic Glass (Amorphous Silica)

igneous
Tumbled Obsidian (Volcanic Glass (Silicon Dioxide)) — igneous

Tumbled Obsidian

Volcanic Glass (Silicon Dioxide)

igneous
Obsidian (in jewelry setting) (Volcanic Glass (Amorphous Silica)) — igneous

Obsidian (in jewelry setting)

Volcanic Glass (Amorphous Silica)

igneous
Obsidian (Volcanic Glass (SiO2 rich)) — igneous

Obsidian

Volcanic Glass (SiO2 rich)

igneous
Obsidian (Obsidian (Extrusive Volcanic Glass)) — igneous

Obsidian

Obsidian (Extrusive Volcanic Glass)

igneous
Obsidian (Volcanic Glass (predominantly SiO2)) — igneous

Obsidian

Volcanic Glass (predominantly SiO2)

igneous
Obsidian (Volcanic Glass (SiO2 rich)) — igneous

Obsidian

Volcanic Glass (SiO2 rich)

igneous
Obsidian (Volcanic glass (SiO2 + impurities)) — igneous

Obsidian

Volcanic glass (SiO2 + impurities)

igneous
Obsidian (Volcanic glass (Mainly SiO2)) — igneous

Obsidian

Volcanic glass (Mainly SiO2)

igneous
Obsidian (Volcanic Glass (Amorphous Silica)) — igneous

Obsidian

Volcanic Glass (Amorphous Silica)

igneous
Obsidian (Obsidian (Volcanic Glass, SiO2)) — igneous

Obsidian

Obsidian (Volcanic Glass, SiO2)

igneous
Obsidian (Volcanic Glass (SiO2 rich)) — Igneous

Obsidian

Volcanic Glass (SiO2 rich)

Igneous
Black Obsidian (Volcanic Glass (SiO2 + impurities)) — igneous

Black Obsidian

Volcanic Glass (SiO2 + impurities)

igneous
Mahogany Obsidian (Volcanic Glass (SiO2 + Fe2O3)) — igneous

Mahogany Obsidian

Volcanic Glass (SiO2 + Fe2O3)

igneous
Obsidian (Volcanic Glass (predominantly SiO2)) — igneous

Obsidian

Volcanic Glass (predominantly SiO2)

igneous
Apache Tear (Hydrated Obsidians (Volcanic Glass)) — igneous

Apache Tear

Hydrated Obsidians (Volcanic Glass)

igneous
Mahogany Obsidian (Volcanic glass (SiO2 + Fe2O3)) — igneous

Mahogany Obsidian

Volcanic glass (SiO2 + Fe2O3)

igneous
Obsidian (Obsidian (Volcanic Glass, SiO2)) — igneous

Obsidian

Obsidian (Volcanic Glass, SiO2)

igneous
Quartz (River Stone) (Silicon Dioxide (SiO2)) — mineral

Quartz (River Stone)

Silicon Dioxide (SiO2)

mineral
Andesite Porphyry (River Cobble) (Porphyritic Andesite) — igneous

Andesite Porphyry (River Cobble)

Porphyritic Andesite

igneous
Obsidian (Volcanic glass (high silica SiO2)) — igneous

Obsidian

Volcanic glass (high silica SiO2)

igneous
Basalt (Mafic Volcanic Rock (composed mainly of Plagioclase, Pyroxene, and Olivine)) — igneous

Basalt

Mafic Volcanic Rock (composed mainly of Plagioclase, Pyroxene, and Olivine)

igneous
Granite with Quartz Vein (Phaneritic Felsic Igneous Rock (composed of Quartz [SiO2], Feldspar, and Mica)) — igneous

Granite with Quartz Vein

Phaneritic Felsic Igneous Rock (composed of Quartz [SiO2], Feldspar, and Mica)

igneous
Amethyst (Agate/Chalcedony variety) (Silicon Dioxide (SiO2) with iron impurities) — mineral

Amethyst (Agate/Chalcedony variety)

Silicon Dioxide (SiO2) with iron impurities

mineral
Quartz on Greenstone (Silicon Dioxide (SiO2) on Altered Igneous Geologic Unit) — metamorphic

Quartz on Greenstone

Silicon Dioxide (SiO2) on Altered Igneous Geologic Unit

metamorphic
Peridotite (Ultramafic intrusive rock (Peridotite)) — Igneous

Peridotite

Ultramafic intrusive rock (Peridotite)

Igneous
Scoria (Lava Rock) (Scoria (Basaltic Scoria)) — Igneous

Scoria (Lava Rock)

Scoria (Basaltic Scoria)

Igneous
Basalt (Basalt) — igneous

Basalt

Basalt

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

Basalt (River Pebble)

Basalt (Mafic Extrusive Igneous Rock)

igneous
Basalt (Mafic Igneous Rock (composed primarily of Pyroxene and Plagioclase Feldspar)) — igneous

Basalt

Mafic Igneous Rock (composed primarily of Pyroxene and Plagioclase Feldspar)

igneous
Obsidian (Volcanic glass (SiO2 - Silicon Dioxide)) — Igneous

Obsidian

Volcanic glass (SiO2 - Silicon Dioxide)

Igneous
Banded Agate (Agate (Cryptocrystalline Quartz, SiO2)) — mineral

Banded Agate

Agate (Cryptocrystalline Quartz, SiO2)

mineral
Granodiorite (Granodiorite (intermediate plutonic rock)) — igneous

Granodiorite

Granodiorite (intermediate plutonic rock)

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

Quartz (Iron-stained)

Silicon Dioxide (SiO2)

mineral
Greenstone (Epidote/Chlorite Rich Rock) (Metabasalt (often contains Epidote Ca2Al2(Fe3+;Al)(SiO4)(Si2O7)O(OH))) — metamorphic

Greenstone (Epidote/Chlorite Rich Rock)

Metabasalt (often contains Epidote Ca2Al2(Fe3+;Al)(SiO4)(Si2O7)O(OH))

metamorphic
Jasper with Hematite inclusions (Silicon Dioxide (SiO2) with Iron Oxide (Fe2O3)) — sedimentary

Jasper with Hematite inclusions

Silicon Dioxide (SiO2) with Iron Oxide (Fe2O3)

sedimentary
Quartz Geode (with possible Manganese or Goethite coating) (Silicon Dioxide (SiO2)) — mineral

Quartz Geode (with possible Manganese or Goethite coating)

Silicon Dioxide (SiO2)

mineral