Rock Identifier

Category

Igneous Rock (Volcanic Glass)

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

Learn about Igneous Rock (Volcanic Glass) in the encyclopedia

Rock Gypsum

Coral Rock

Asphalt Rock

Rock Salt

Calc-Silicate Rock

Calc-Silicate Rock

Talc-carbonate Rock

Talc-carbonate Rock

Black Obsidian

Obsidian

Pink Obsidian

Sideromelane

Carbonatite

Tachylite

Quartz (Silicon Dioxide (SiO2)) — mineral

Quartz

Silicon Dioxide (SiO2)

Banded Rhyolite (likely Green Jasper/Agate variety) (Silicon Dioxide (SiO2) with mineral inclusions) — igneous

Banded Rhyolite (likely Green Jasper/Agate variety)

Silicon Dioxide (SiO2) with mineral inclusions

Brecciated agate/chalcedony (Microcrystalline quartz (SiO₂), chiefly chalcedony with possible quartz and iron-oxide inclusions) — mineral

Brecciated agate/chalcedony

Microcrystalline quartz (SiO₂), chiefly chalcedony with possible quartz and iron-oxide inclusions

Scoria (Lava Rock) (Mafic extrusive volcanic rock (Scientific formula varies based on mineral content: primarily SiO2, MgO, and FeO)) — igneous

Scoria (Lava Rock)

Mafic extrusive volcanic rock (Scientific formula varies based on mineral content: primarily SiO2, MgO, and FeO)

Quartz vein in dark host rock (Quartz (SiO₂), likely in basalt, gabbro, or altered mafic rock) — mineral

Quartz vein in dark host rock

Quartz (SiO₂), likely in basalt, gabbro, or altered mafic rock

Basalt with Quartz/Calcite Inclusions (Mafic Volcanic Rock (Fe-Mg silicate rich)) — igneous

Basalt with Quartz/Calcite Inclusions

Mafic Volcanic Rock (Fe-Mg silicate rich)

Likely obsidian (possibly tektite or slag glass) (Volcanic glass; primarily SiO₂, noncrystalline) — igneous

Likely obsidian (possibly tektite or slag glass)

Volcanic glass; primarily SiO₂, noncrystalline

Quartz (Silicon Dioxide (SiO2)) — mineral

Quartz

Silicon Dioxide (SiO2)

Quartz (Milky Quartz vein fragment) (Silicon Dioxide (SiO2)) — mineral

Quartz (Milky Quartz vein fragment)

Silicon Dioxide (SiO2)

Greenstone (Greenschist / Greenstone (Epimetamorphic Rock)) — metamorphic

Greenstone

Greenschist / Greenstone (Epimetamorphic Rock)

Vesicular Basalt (Vesicular Basalt) — igneous

Vesicular Basalt

Vesicular Basalt

Vesicular Basalt (Extrusive mafic igneous rock; primarily (Ca,Na)(Mg,Fe,Al,Si)2O6 (Pyroxene) and (Ca,Na)Al(Al,Si)Si2O8 (Plagioclase Feldspar)) — igneous

Vesicular Basalt

Extrusive mafic igneous rock; primarily (Ca,Na)(Mg,Fe,Al,Si)2O6 (Pyroxene) and (Ca,Na)Al(Al,Si)Si2O8 (Plagioclase Feldspar)

Mixed collection of Quartz varieties, Chalcedony, and metamorphic pebbles (Mixed gemstones (primarily Silicon Dioxide - SiO2)) — mineral

Mixed collection of Quartz varieties, Chalcedony, and metamorphic pebbles

Mixed gemstones (primarily Silicon Dioxide - SiO2)

Red Jasper (Quartz) (Silicon Dioxide (SiO2) with Iron impurities) — sedimentary

Red Jasper (Quartz)

Silicon Dioxide (SiO2) with Iron impurities

Quartz Vug / Druzy Quartz (Silicon Dioxide (SiO2)) — mineral

Quartz Vug / Druzy Quartz

Silicon Dioxide (SiO2)

Quartz (Milky or Druzy Quartz) (Silicon Dioxide (SiO2)) — mineral

Quartz (Milky or Druzy Quartz)

Silicon Dioxide (SiO2)

Chalcedony (likely agate/chert fragment) (Microcrystalline quartz, SiO₂) — mineral

Chalcedony (likely agate/chert fragment)

Microcrystalline quartz, SiO₂

Quartz (Silicon Dioxide (SiO2)) — mineral

Quartz

Silicon Dioxide (SiO2)

Jasp-Agate (Cryptocrystalline Quartz (SiO2) with Iron Oxide inclusions) — sedimentary

Jasp-Agate

Cryptocrystalline Quartz (SiO2) with Iron Oxide inclusions

Basalt (Greenstone/Trap Rock) (Basalt (dominated by plagioclase feldspar and pyroxene)) — igneous

Basalt (Greenstone/Trap Rock)

Basalt (dominated by plagioclase feldspar and pyroxene)

Unidentified Rock Fragment (Unknown) — Rock

Unidentified Rock Fragment

Unknown

Diorite (Phaneritic Intermediate Plutonic Rock (Diorite)) — igneous

Diorite

Phaneritic Intermediate Plutonic Rock (Diorite)

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

Obsidian

Obsidian (Volcanic Glass, primarily SiO2)

Quartz with Host Rock Matrix (Silicon Dioxide (SiO2)) — mineral

Quartz with Host Rock Matrix

Silicon Dioxide (SiO2)

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

Clear Quartz / Rock Crystal

Silicon Dioxide (SiO2)

Pink Tumbled Agate (Silicon Dioxide (SiO2) with dye) — mineral

Pink Tumbled Agate

Silicon Dioxide (SiO2) with dye

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

Clear Quartz

Quartz (Silicon Dioxide, SiO2)

Basalt (Basalt) — igneous

Basalt

Basalt

Diorite (River Cobble) (Phaneritic intermediate plutonic rock) — igneous

Diorite (River Cobble)

Phaneritic intermediate plutonic rock

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

Basalt (River or Beach Pebble)

Basalt (Mafic Extrusive Igneous Rock)

Greenstone Porphyry (Altered Porphyritic Andesite/Basalt) — igneous

Greenstone Porphyry

Altered Porphyritic Andesite/Basalt

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

Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Glass (Amorphous Silicon Dioxide (SiO2)) — mineraloid

Glass

Amorphous Silicon Dioxide (SiO2)

Quartz-rich mineral fragment (Quartz (silicon dioxide, SiO₂), possibly milky quartz) — mineral

Quartz-rich mineral fragment

Quartz (silicon dioxide, SiO₂), possibly milky quartz

Quartz Geode (Silicon Dioxide (SiO2) within a geode) — mineral

Quartz Geode

Silicon Dioxide (SiO2) within a geode

Greenstone / Diabase Porphyry (Porphyritic Diabase (Micro-gabbro)) — Igneous

Greenstone / Diabase Porphyry

Porphyritic Diabase (Micro-gabbro)

Quartz Pebble (Silicon Dioxide (SiO2)) — mineral

Quartz Pebble

Silicon Dioxide (SiO2)

River Rock (Basalt) (Basalt (SiO2 range: 45-52%)) — igneous

River Rock (Basalt)

Basalt (SiO2 range: 45-52%)

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

Granite

Granite (Phaneritic Quartz-Feldspar Plutonic Rock)

Coarse-grained granite or granitic pegmatite (Granite; primarily quartz (SiO₂), feldspar, and mica/amphibole) — igneous

Coarse-grained granite or granitic pegmatite

Granite; primarily quartz (SiO₂), feldspar, and mica/amphibole

Weathered iron-rich rock, possibly laterite or altered basalt (Probable ferruginous basalt/lat eritic material; exact identification requires testing) — igneous

Weathered iron-rich rock, possibly laterite or altered basalt

Probable ferruginous basalt/lat eritic material; exact identification requires testing

Basalt (Aphanitic mafic volcanic rock (primarily plagioclase feldspar and pyroxene)) — igneous

Basalt

Aphanitic mafic volcanic rock (primarily plagioclase feldspar and pyroxene)