Basalt
Basalt
Category
Browse mineral in igneous rock specimens identified by the Rock Identifier community.
Basalt
Basalt
Pumice
Pumice (Amorphous volcanic glass)
Basalt
Basalt (dominated by Plagioclase Feldspar and Pyroxene)
Basalt
Basalt (composition of Plagioclase feldspar and Pyroxene)
Basalt
Basalt
Basalt
Basalt
Smoky Quartz in Matrix
Silicon dioxide (SiO2) within Pegmatite/Gneiss
Arsenopyrite in Quartz Matrix
Arsenopyrite (FeAsS) with Quartz (SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Amethyst Quartz Druse
Silicon Dioxide (SiO2) with iron impurities
Quartz Druzy Geode
Silicon Dioxide (SiO2) - Crystalline Variety
Pumice
Pumice (Felsic volcanic rock)
Lava Rock (Scoria)
Scoria (Basaltic Scoria)
Basalt
Basalt (Mafic volcanic rock)
Granite
Granite (Mainly Quartz, Alkali Feldspar, and Plagioclase)
Basalt
Basalt (Mafic volcanic rock)
Labradorite (Larvikite variety)
Ternary feldspar (Anorthoclase), (Na,K)AlSi3O8
Pumice
Pumice (Vesicular volcanic glass / Rhyolite or Trachyte)
Scoria (Basaltic)
Vesicular Basalt
Granite
Granite (composed of Quartz, Feldspar, and Mica/Amphibole)
Basalt (Vesicular)
Basalt (Extrusive Igneous)
Quartz (likely macrocrystalline variety)
Quartz (SiO₂)
Schist
Schist
Epidote
Epidote Group (Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH))
Quartz Geode
Silicon Dioxide (SiO2) in a Geode body
Sandstone
Arenite (SiO2 predominantly)
Basalt with Olivine inclusion
Mafic Volcanic Basalt (Fe,Mg)2SiO4
Pumice (Volcanic Rock)
Vesicular volcanic rock (composed largely of amorphous volcanic glass)
Basalt with Quartz Veining
Basalt (Mafic Volcanic Rock with SiO2)
Basalt
Mafic Volcanic Rock (Primarily Plagioclase feldspar and Pyroxene)
Porphyritic Basalt (Chinese Writing Stone)
Porphyritic Basalt or Porphyritic Andesite
Basalt with Quartz Veins
Vesicular or aphanitic Basalt with SiO2 (Quartz) intrusions
Pumice
Vesicular volcanic glass
Basalt (Weathered Pebble)
Extrusive mafic rock (primarily Plagioclase Feldspar and Pyroxene)
Quartz Geode
Silicon Dioxide (SiO2)
Sandstone (Tumbled/River Pebble)
Arenite (composed primarily of SiO2)
White Topaz
Al2SiO4(F,OH)2
Porphyritic Basalt or Andesite
Porphyritic Basalt/Andesite
Labradorite (Larvikite variety)
Plagioclase Feldspar (Na,Ca)(Al,Si)4O8 with Monzonite/Syenite matrix
Bumblebee Jasper
Volcanic Tuff (mixture of Quartz, Sulfur, Hematite, and Orpiment)
Shale or Slaty Mudstone
Argillaceous sedimentary rock
Amethyst
Quartz variety; chemical formula: SiO₂ (silicon dioxide) with Fe³⁺ impurities