Rock Identifier

Category

Igneous Rock (Volcanic Glass)

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

Black Obsidian (Volcanic Glass (Primary composition: SiO2 - Silicon Dioxide)) — igneous

Black Obsidian

Volcanic Glass (Primary composition: SiO2 - Silicon Dioxide)

Obsidian (Volcanic Glass (Primary composition: SiO2 - Silicon Dioxide)) — Igneous

Obsidian

Volcanic Glass (Primary composition: SiO2 - Silicon Dioxide)

Obsidian (Volcanic glass (primary composition: SiO2)) — igneous

Obsidian

Volcanic glass (primary composition: SiO2)

Mahogany Obsidian Arrowhead (Obsidian (volcanic glass) with Hematite inclusions) — igneous

Mahogany Obsidian Arrowhead

Obsidian (volcanic glass) with Hematite inclusions

Granite (Granite (Phaneritic Acidic Igneous Rock)) — igneous

Granite

Granite (Phaneritic Acidic Igneous Rock)

Obsidian (Volcanic Glass (70% or more SiO2)) — igneous

Obsidian

Volcanic Glass (70% or more SiO2)

Porphyritic Basalt (Chinese Writing Stone/Flower Stone) (Porphyritic Basalt (primarily Plagioclase Feldspar in a Mafic groundmass)) — igneous

Porphyritic Basalt (Chinese Writing Stone/Flower Stone)

Porphyritic Basalt (primarily Plagioclase Feldspar in a Mafic groundmass)

Basalt (Vesicular) (Vesicular Basalt) — Igneous

Basalt (Vesicular)

Vesicular Basalt

Agate Geode (Chalcedony (cryptocrystalline SiO2)) — mineral

Agate Geode

Chalcedony (cryptocrystalline SiO2)

Peridotite (with Olivine and Pyroxene) (Ultramafic Magmatic Rock (Primary minerals: (Mg, Fe)2SiO4 and (Ca, Mg, Fe)2Si2O6)) — igneous

Peridotite (with Olivine and Pyroxene)

Ultramafic Magmatic Rock (Primary minerals: (Mg, Fe)2SiO4 and (Ca, Mg, Fe)2Si2O6)

Clear Quartz (Rock Crystal) (Silicon Dioxide (SiO2)) — mineral

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Basalt with Epidote/Chlorite (Amygdaloidal Basalt (SiO2 with (Ca2(Al2,Fe)(SiO4)(Si2O7)O(OH)))) — igneous

Basalt with Epidote/Chlorite

Amygdaloidal Basalt (SiO2 with (Ca2(Al2,Fe)(SiO4)(Si2O7)O(OH)))

Jasper with Quartz Veining (Silicon Dioxide (SiO2) - Microcrystalline Quartz) — sedimentary

Jasper with Quartz Veining

Silicon Dioxide (SiO2) - Microcrystalline Quartz

Yellow Jasper (Silicon Dioxide (SiO2) with iron hydroxides (Goethite)) — sedimentary

Yellow Jasper

Silicon Dioxide (SiO2) with iron hydroxides (Goethite)

Milky Quartz Vein in Host Rock (Silicon Dioxide (SiO2)) — Mineral

Milky Quartz Vein in Host Rock

Silicon Dioxide (SiO2)

Smoky Quartz (Silicon Dioxide (SiO2)) — mineral

Smoky Quartz

Silicon Dioxide (SiO2)

Clear Quartz (Silicon Dioxide (SiO2)) — mineral

Clear Quartz

Silicon Dioxide (SiO2)

Basalt (Basalt (Mafic Extrusive)) — igneous

Basalt

Basalt (Mafic Extrusive)

Basalt (Basalt) — igneous

Basalt

Basalt

Obsidian (specifically Mahogany Obsidian) (Volcanic glass (high silica content, SiO2)) — igneous

Obsidian (specifically Mahogany Obsidian)

Volcanic glass (high silica content, SiO2)

Red Jasper (Polished) (Silicon Dioxide (SiO2) with Hematite inclusions) — sedimentary

Red Jasper (Polished)

Silicon Dioxide (SiO2) with Hematite inclusions

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

Milky Quartz (Vein Quartz)

Silicon Dioxide (SiO2)

Amethyst (Silicon Dioxide with trace Iron (SiO2)) — mineral

Amethyst

Silicon Dioxide with trace Iron (SiO2)

Obsidian (Volcanic Glass (Amorphous Silicon Dioxide , SiO2)) — igneous

Obsidian

Volcanic Glass (Amorphous Silicon Dioxide , SiO2)

Chalcedony (Quartz Nodule) (Silicon Dioxide (SiO2)) — mineral

Chalcedony (Quartz Nodule)

Silicon Dioxide (SiO2)

Muscovite Mica (Muscovite / KAl2(AlSi3O10)(OH)2) — mineral

Muscovite Mica

Muscovite / KAl2(AlSi3O10)(OH)2

Dalmatian Jasper (or Dalmatian Stone) (Dalmatian Stone (A peralkaline felsite composed of feldspar, quartz, and sodic amphibole)) — igneous

Dalmatian Jasper (or Dalmatian Stone)

Dalmatian Stone (A peralkaline felsite composed of feldspar, quartz, and sodic amphibole)

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

Obsidian

Volcanic glass (SiO2 - Silicon Dioxide)

Diabase (Trap Rock) (Diabase (also known as Dolerite)) — igneous

Diabase (Trap Rock)

Diabase (also known as Dolerite)

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

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Smoky Quartz (Apache Tear Variety) (Silicon dioxide (SiO2) - Volcanic Glass) — igneous

Smoky Quartz (Apache Tear Variety)

Silicon dioxide (SiO2) - Volcanic Glass

Granite Pebble (Pink Granite) (Phaneritic Igneous Rock (primarily Quartz, Potassium Feldspar, and Plagioclase)) — igneous

Granite Pebble (Pink Granite)

Phaneritic Igneous Rock (primarily Quartz, Potassium Feldspar, and Plagioclase)

Gold Sheen Obsidian (Obsidian (volcanic glass with SiO2 + gas inclusions)) — igneous

Gold Sheen Obsidian

Obsidian (volcanic glass with SiO2 + gas inclusions)

Quartz Druzy Geode Fragment (Silicon Dioxide (SiO2)) — mineral

Quartz Druzy Geode Fragment

Silicon Dioxide (SiO2)

Jasper in Basalt Matrix (Silicon Dioxide (SiO2) with impurities; Chalcedony) — sedimentary (secondary mineral) within igneous

Jasper in Basalt Matrix

Silicon Dioxide (SiO2) with impurities; Chalcedony

sedimentary (secondary mineral) within igneous

Milky Quartz (Silicon Dioxide (SiO2)) — mineral

Milky Quartz

Silicon Dioxide (SiO2)

Amygdaloidal Basalt (Amygdaloidal Basalt (extrusive volcanic rock with mineral inclusions)) — igneous

Amygdaloidal Basalt

Amygdaloidal Basalt (extrusive volcanic rock with mineral inclusions)

Basalt River Pebble (Aphanitic Mafic Basalt) — igneous

Basalt River Pebble

Aphanitic Mafic Basalt

Chalcedony (Quartz Var.) (Silicon Dioxide (SiO2)) — mineral

Chalcedony (Quartz Var.)

Silicon Dioxide (SiO2)

Obsidian (Apache Tear) (Volcanic Glass (composed mainly of SiO2)) — igneous

Obsidian (Apache Tear)

Volcanic Glass (composed mainly of SiO2)

Basalt (Extrusive mafic igneous rock; primarily (Ca,Na)(Mg,Fe,Al,Si)2O6 with (Ca,Na)(Al,Si)4O8) — igneous

Basalt

Extrusive mafic igneous rock; primarily (Ca,Na)(Mg,Fe,Al,Si)2O6 with (Ca,Na)(Al,Si)4O8

Basalt (Vesicular and Ropey) (Vesicular Basalt / Pahoehoe Basalt) — igneous

Basalt (Vesicular and Ropey)

Vesicular Basalt / Pahoehoe Basalt