Apache Tear
Hydrated Obsidian (Volcanic Glass)
Category
Browse sedimentary and igneous (mixed) specimens identified by the Rock Identifier community.
Apache Tear
Hydrated Obsidian (Volcanic Glass)
Yooperlite
Fluorescent Sodalite-bearing Syenite
Porphyritic Basalt (or Porphyry)
Porphyritic Basalt (Mafic volcanic rock with phenocrysts)
Snowflake Obsidian
Vitreous volcanic silicate (SiO2 with Cristobalite inclusions)
Granite (specifically Pink Granite)
Phaneritic Plutonic Rock (High Potassium Feldspar Granite)
Granitic Pegmatite
Granitic Pegmatite with Quartz and Feldspar
Granite
Granite (Felsic Plutonic Rock, consisting primarily of Quartz, Feldspar, and Mica)
Basalt with Quartz/Calcite Veins
Amygdaloidal Basalt (SiO2 or CaCO3 inclusions)
Granite Pebble
Granite (Phaneritic intrusive igneous rock comprising Quartz, Feldspar, and Mica)
Granite
Phaneritic intrusive igneous rock (composed mainly of Quartz SiO2, Feldspar KAlSi3O8, and Biotite/Mica)
Mahogany Obsidian
Volcanic Glass with Hematite inclusions (SiO2 + Fe2O3)
Granite
Phaneritic Intrusive Igneous Rock (primarily Quartz, Feldspar, and Mica)
Basalt
Basalt (Aphanitic Mafic Igneous Rock)
Mica (Biotite and Muscovite) in Matrix
Potassium aluminum silicate with iron/magnesium (KAl2(AlSi3O10)(F,OH)2 / K(Mg,Fe)3AlSi3O10(F,OH)2)
Basalt with Quartz/Epidote Vein
Mafic volcanic rock (formula primarily (Mg, Fe)2SiO4 and CaAl2Si2O8)
Basalt (Porphyritic Basalt)
Porphyritic Basalt (Mafic volcanic rock)
Diorite
Intrusive Igneous Rock (Intermediate Composition)
Granite Cobble
Felsic intrusive igneous rock (composition: SiO₂ with KAlSi₃O₈, NaAlSi₃O₈, and CaAl₂Si₂O₈)
Porfido (Porphyritic Rock)
Porphyry (often Rhyolitic or Andesitic)
Mahogany Obsidian
Volcanic Glass with Hematite/Magnetite (SiO2 + Fe2O3)
Obsidian
Obsidian (Amorphous volcanic glass, SiO2 with impurities)
Basalt (Water-worn Pebble)
Basalt (Mafic Extrusive Igneous Rock)
Granite with Biotite and Quartz
Phaneritic Felsic Igneous Rock (composed of SiO2, KAlSi3O8, and K(Mg,Fe)3AlSi3O10(OH)2)
Black Obsidian
Obsidian (Volcanic Glass), primarily SiO2 (Silicon Dioxide)
Basalt
Basalt (Mafic volcanic rock)
Larvikite
Larvikite (Anorthoclase-rich Monzonite)
Obsidian
Obsidian (Volcanic Glass), primarily SiO2 (Silicon Dioxide)
Basalt (River Stone)
Aphanitic Mafic Igneous Rock
Granite Cobble
Phaneritic Felsic Igneous Rock
Blue Sapphire (faceted in jewelry)
Corundum (Al2O3)
Mahogany Obsidian
Volcanic Glass with Hematite inclusions (SiO2)
Granite
Phaneritic Igneous Rock (Granite)
Basalt
Basalt (Mafic volcanic rock)
Vesicular Basalt with Amygdules
Amygdaloidal Basalt
Granodiorite Pebble
Granodiorite (Intermediate intrusive igneous rock)
Mica
Phlogopite or Biotite group (KMg3(AlSi3O10)(F,OH)2 / K(Mg,Fe)3AlSi3O10(OH)2)
Basalt River Stone
Basalt (Mafic volcanic rock, primarily Plagioclase and Pyroxene)
Porphyritic Rhyolite
Rhyolite (Porphyritic texture)
Diamond in Kimberlite
Diamond (C in Kimberlite Matrix)
Basalt
Basalt (Mafic Extrusive Igneous Rock)
Granite
Phaneritic Felsic Igneous Rock
Pumice
Vesicular Rhyolite / Pumice