Muscovite Mica
Muscovite KAl2(AlSi3O10)(OH)2
Category
Browse igneous rock specimens identified by the Rock Identifier community.
Muscovite Mica
Muscovite KAl2(AlSi3O10)(OH)2
Biotite Mica
Biotite (K(Mg,Fe)3AlSi3O10(OH,F)2)
Blue Sapphire
Corundum (Al2O3)
Granite
Granite (Phaneritic Quartz-Feldspar Felsic Rock)
Basalt
Basalt (Mafic volcanic rock)
Pumice
Pumice (Felsic volcanic rock)
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
Quartz Pebble
Silicon Dioxide (SiO2)
Pumice and Scoria
Vesicular Volcanic Ejecta (Rhyolite/Andesite/Basalt)
Chalcedony (Agate)
Silicon Dioxide (SiO2)
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
Greenstone
Metabasalt (Greenstone Facies)
Amethyst
Amethyst (Silicon Dioxide - SiO2)
River Stone (Chalcedony/Jasper variety)
Microcrystalline Quartz (SiO2)
Basalt with Epidote (Porphyry)
Basalt (with inclusions of Epidote/Feldspar)
Clear Quartz (Rock Crystal)
Quartz (Silicon Dioxide, SiO2)
Quartz with Oxides
Silicon Dioxide (SiO2)
Snowflake Obsidian (or similar porphyritic volcanic rock)
Obsidian with Spherulites (if glassy), or Porphyritic Rhyolite/Andesite (if crystalline groundmass)
Granite
Felsic Plutonic Rock (Granite)
Amethyst
Silicon Dioxide (SiO2) with iron impurities
Moonstone
Orthoclase (KAlSi3O8) with Albite (NaAlSi3O8) inclusions
Quartz
Silicon Dioxide (SiO2)
Quartz (Grain)
Silicon Dioxide (SiO2)
Clear Quartz
Silicon Dioxide (SiO2)
Quartz
Silicon dioxide (SiO2)
Greenstone
Greenschist (composed of actinolite, chlorite, and epidote)
Gneiss
Gneiss (High-grade Metamorphic Rock)
Basalt with Mineral Vein (Cobble)
Basalt (with likely Quartz/Calcite vein)
Yellow Quartz Pebble
Silicon Dioxide (SiO2)
Granodiorite
Granodiorite (Intermediate to Felsic Intrusive Rock)
Pink Granite / Gneiss
Felsic Plutonic Rock (Granite) with Gneissic banding
Vesicular Basalt
Amygdaloidal Basalt (Mafic extrusive volcanic rock)
River Stone (Basalt or Siltstone)
Mafic Volcanic Rock or Clastic Sedimentary Rock
Yellow Quartz (Citrine/Yellow Jasper mix)
Silicon Dioxide (SiO2)
Basalt with Quartz Vein
Basalt (Mafic volcanic rock) with secondary Quartz (SiO2) intrusion
Granite
Granite (Felsic Plutonic Rock)
Basalt
Basalt (Mafic volcanic rock)
Peridotite
Ultramafic intrusive rock (Peridotite)
Basalt
Basalt (extrusive volcanic rock)
Basalt with Iron Oxide staining
Basalt (Mafic volcanic rock)
Granite
Granite (Felsic Plutonic Rock)
Basalt
Basalt (Mafic volcanic rock)