Rhyolite
Rhyolite (Extrusive Felsic Igneous Rock)
Category
Browse mineral on igneous rock specimens identified by the Rock Identifier community.
Rhyolite
Rhyolite (Extrusive Felsic Igneous Rock)
Granite
Granite (Silicic Intrusive Igneous Rock)
Basalt River Stone
Basalt (Aphanitic Mafic Igneous Rock)
Granite fragment
Phaneritic Igneous Rock (Granitic composition)
Pumice
Vesicular Rhyolite / Glassy Igneous Rock
Basalt
Basalt (Extrusive Mafic Igneous Rock)
Diorite
Diorite (an intermediate intrusive igneous rock)
Granite
Phaneritic Felsic Igneous Rock (Granite)
Pink Granite
Granite (Phaneritic intrusive rock rich in K-feldspar)
Rutilated Quartz
Quartz (SiO2) with Rutile (TiO2) inclusions
Basalt
Mafic Igneous Rock (primarily Plagioclase and Pyroxene)
Pumice
Pumicite (Amorphous glass with varying chemical composition, often rhyolitic)
Obsidian (Black Obsidian)
Amorphous volcanic glass (primarily SiO2)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
Magnetite
Magnetite (Fe3O4)
Scoria
Extrusive Igneous Rock (Basaltic/Andesitic Composition)
Magnetite Sand (Black Sand)
Magnetite (Fe3O4)
Arsenopyrite in Quartz/Host Rock
Arsenopyrite (FeAsS)
Serpentine
Serpentinite (rock), Serpentine group minerals (e.g., Antigorite, Lizardite, Chrysotile)
Basalt
Mafic extrusive volcanic rock (composed primarily of Plagioclase feldspar and Pyroxene)
Magnetite
Magnetite (Fe3O4)
Granite
Granite (a common rock type, not a single mineral; composed primarily of Quartz, Feldspar (Orthoclase and Plagioclase), and Mica (Biotite and/or Muscovite) and/or Amphibole)
Basalt
Basalt (Mafic volcanic rock)
Sandstone
Arenite (primarily SiO2)
Basalt
Basalt (dominated by plagioclase feldspar and pyroxene minerals)
Quartz Geode/Cluster
Quartz (SiO2)
Druzy Quartz on Chert/Chalcedony
Silicon Dioxide (SiO2)
N/A - Non-Geological Item
Granodiorite
Granodiorite
Quartz
Quartz (SiO₂)
Banded Gneiss
Gneiss (High-grade regional metamorphic rock)
Yellow Calcite
Calcite (Calcium Carbonate, CaCO3)
Fluorite and Rose Quartz
Fluorite (CaF2), Rose Quartz (SiO2)
Pink Granite
Felsic Plutonic Rock (primarily Quartz, Potassium Feldspar, and Plagioclase)
Granite Gneiss
High-grade regional metamorphic rock (Quartz-Feldspar Gneiss)
Granite
Granite (composed primarily of Quartz SiO2, Feldspar (KAlSi3O8), and Mica)
Basalt
Mafic Igneous Rock (composed primarily of Pyroxene and Plagioclase Feldspar)
Conglomerate with Quartz Inclusions
Conglomerate (clastic sedimentary rock) with internal Quartz (SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Breciated Jasper
Silicon Dioxide (SiO2) with iron oxide inclusions
Arkosic Sandstone (or Conglomeritic Sandstone fragment)
Arkose (rich in feldspar)