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

Demitasse Granite (Diorite-Granite transition) (Intermediate Plutonic Rock (Granodiorite/Diorite mix)) — igneous

Demitasse Granite (Diorite-Granite transition)

Intermediate Plutonic Rock (Granodiorite/Diorite mix)

Diorite with Xenolith (Phaneritic Intermediate Plutonic Rock) — igneous

Diorite with Xenolith

Phaneritic Intermediate Plutonic Rock

Basalt (Water-worn pebble) (Basalt (Mafic Extrusive Rock)) — igneous

Basalt (Water-worn pebble)

Basalt (Mafic Extrusive Rock)

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

Quartz (Druzy)

Silicon Dioxide (SiO2)

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

Tumbled Clear Quartz

Silicon Dioxide (SiO2)

Rounded basalt cobble (probable) (Basalt; fine-grained mafic volcanic rock, chiefly plagioclase and pyroxene) — igneous

Rounded basalt cobble (probable)

Basalt; fine-grained mafic volcanic rock, chiefly plagioclase and pyroxene

Red Scoria (Scoria (vesicular basaltic rock)) — igneous

Red Scoria

Scoria (vesicular basaltic rock)

Likely polished dark stone or glassy mineral bead (Indeterminate; possibly obsidian, hematite, or a dark agate) — mineral

Likely polished dark stone or glassy mineral bead

Indeterminate; possibly obsidian, hematite, or a dark agate

Weathered dark rock fragment (Indeterminate; possibly basalt or iron-rich volcanic rock) — igneous

Weathered dark rock fragment

Indeterminate; possibly basalt or iron-rich volcanic rock

Faceted Clear Quartz (Rock Crystal) (Silicon Dioxide (SiO2)) — gemstone

Faceted Clear Quartz (Rock Crystal)

Silicon Dioxide (SiO2)

Basalt (Basalt) — igneous

Basalt

Basalt

Quartz Pebble (Silicon Dioxide (SiO2)) — mineral

Quartz Pebble

Silicon Dioxide (SiO2)

Snowflake Obsidian (Volcanic Glass with Cristobalite Inclusions (SiO2)) — igneous

Snowflake Obsidian

Volcanic Glass with Cristobalite Inclusions (SiO2)

Amethyst (Silicon dioxide (variant with ferric iron impurities), SiO2) — mineral

Amethyst

Silicon dioxide (variant with ferric iron impurities), SiO2

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

Andesite Porphyry (River Cobble)

Porphyritic Andesite

Basalt with Jasper Veining (Basaltic Rock with Cryptocrystalline Quartz (SiO2)) — igneous

Basalt with Jasper Veining

Basaltic Rock with Cryptocrystalline Quartz (SiO2)

Basalt with Quartz/Feldspar Inclusion (Basalt (containing Silicate minerals such as SiO2 and (Ca,Na)(Al,Si)4O8)) — igneous

Basalt with Quartz/Feldspar Inclusion

Basalt (containing Silicate minerals such as SiO2 and (Ca,Na)(Al,Si)4O8)

Scoria (Scoria (Vesicular Basalt/Andesite)) — igneous

Scoria

Scoria (Vesicular Basalt/Andesite)

Porphyritic Basalt (with Olivine or Quartz phenocryst) (Porphyritic Basalt (Mafic Extrusive)) — igneous

Porphyritic Basalt (with Olivine or Quartz phenocryst)

Porphyritic Basalt (Mafic Extrusive)

Polished agate slice (Agate, a banded variety of chalcedony (microcrystalline SiO₂)) — mineral

Polished agate slice

Agate, a banded variety of chalcedony (microcrystalline SiO₂)

Jasper (Chert (Silica: SiO2)) — sedimentary

Jasper

Chert (Silica: SiO2)

Quartz with Feldspar (Silicon Dioxide (SiO2) with Potassium Feldspar (KAlSi3O8)) — igneous

Quartz with Feldspar

Silicon Dioxide (SiO2) with Potassium Feldspar (KAlSi3O8)

Milky Quartz (Silicon Dioxide (SiO2)) — mineral

Milky Quartz

Silicon Dioxide (SiO2)

Peridot (likely, based on color and appearance) (Olivine group mineral, specifically (Mg,Fe)2SiO4 (Forsterite-Fayalite solid solution series)) — Mineral

Peridot (likely, based on color and appearance)

Olivine group mineral, specifically (Mg,Fe)2SiO4 (Forsterite-Fayalite solid solution series)

Milky Quartz (with trace inclusions) (Silicon Dioxide (SiO2)) — mineral

Milky Quartz (with trace inclusions)

Silicon Dioxide (SiO2)

Amygdaloidal Basalt (Vesicular-Amygdaloidal Basalt (Mafic Extrusive)) — igneous

Amygdaloidal Basalt

Vesicular-Amygdaloidal Basalt (Mafic Extrusive)

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

Milky Quartz

Quartz (Silicon Dioxide, SiO2)

Quartz Pebble (Silicon Dioxide (SiO2)) — mineral

Quartz Pebble

Silicon Dioxide (SiO2)

Basalt (Basalt (Mafic volcanic rock, primarily Plagioclase and Pyroxene)) — igneous

Basalt

Basalt (Mafic volcanic rock, primarily Plagioclase and Pyroxene)

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

Diorite

Diorite (Intermediate intrusive igneous rock)

Granite / Quartz Vein Rock (Granitoid with Quartz (SiO2)) — igneous

Granite / Quartz Vein Rock

Granitoid with Quartz (SiO2)

Basalt with Epidote Veining (Basalt (Mafic Extrusive Rock) with Ca2(Al,Fe)3(SiO4)3(OH)) — igneous

Basalt with Epidote Veining

Basalt (Mafic Extrusive Rock) with Ca2(Al,Fe)3(SiO4)3(OH)

Basalt (River Pebble) (Basalt) — igneous

Basalt (River Pebble)

Basalt

Basalt Pebble with Epidote/Olivine (Vitreous Basalt (SiO2 with Ca/Mg/Fe silicates)) — igneous

Basalt Pebble with Epidote/Olivine

Vitreous Basalt (SiO2 with Ca/Mg/Fe silicates)

Quartz Pebble (Silicon Dioxide (SiO2)) — mineral

Quartz Pebble

Silicon Dioxide (SiO2)

Milky Quartz (Silicon Dioxide (SiO2)) — mineral

Milky Quartz

Silicon Dioxide (SiO2)

Basalt (Basalt (Mafic Extrusive)) — igneous

Basalt

Basalt (Mafic Extrusive)

Black Obsidian (Obsidian (Volcanic Glass, SiO2 + impurity)) — igneous

Black Obsidian

Obsidian (Volcanic Glass, SiO2 + impurity)

Milky Quartz (Silicon Dioxide (SiO2)) — mineral

Milky Quartz

Silicon Dioxide (SiO2)

Quartz Pebble (Silicon Dioxide (SiO2)) — mineral

Quartz Pebble

Silicon Dioxide (SiO2)

Vesicular Basalt (Vesicular Basalt (rich in silicate minerals mostly Plagioclase and Pyroxene)) — igneous

Vesicular Basalt

Vesicular Basalt (rich in silicate minerals mostly Plagioclase and Pyroxene)

Granite (with Quartz Vein and Biotite) (Granite (Plutonic Igneous Rock)) — igneous

Granite (with Quartz Vein and Biotite)

Granite (Plutonic Igneous Rock)