Basalt (Polished)
Basalt (Mafic Extrusive Igneous Rock)
Category
Browse mineral in igneous rock specimens identified by the Rock Identifier community.
Basalt (Polished)
Basalt (Mafic Extrusive Igneous Rock)
Sandstone
Arenite (SiO2 dominant)
Diorite (Salt and Pepper Rock)
Phaneritic Plutonic Diorite; chemical composition roughly 52-63% silica (SiO2)
Green Calcite
Calcium Carbonate (CaCO3)
Labradorite
Labradorite (a variety of Plagioclase Feldspar), Na(AlSi3O8) to Ca(Al2Si2O8)
Pumice
Pumicite (Amorphous glass with varying chemical composition, often rhyolitic)
White Quartz Pebble
Silicon Dioxide (SiO2)
Chinese Writing Stone
Porphyritic Basalt or Porphyritic Andesite with Feldspar phenocrysts (SiO2-rich Silicates)
Quartz
Silicon Dioxide (SiO2)
Sandstone (Micaceous)
Clastic Sedimentary Rock (primarily SiO2 with Mica)
Black Obsidian
Obsidian (Volcanic glass), 70–75% SiO2
Quartz Pebble (often referred to as 'Sea Glass' or 'River Stone' when worn smooth)
Silicon Dioxide (SiO2)
Pyrite
Iron Sulfide (FeS2)
Quartz (Smoky/Milky variety)
Silicon Dioxide (SiO2)
Quartz (Citrine or Smoky variant)
Silicon Dioxide (SiO2)
Quartz (Milky Quartz)
Silicon Dioxide (SiO2)
Dalmatian Stone
Dalmatian Jasper (Aplitic Perthite)
Orbicular Rhyolite (Rainforest Jasper)
Rhyolite containing Spherulites (SiO2 with impurities)
Milky Quartz Pebble
Silicon Dioxide (SiO2)
Gneiss
Gneiss (High-grade regional metamorphic rock)
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
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)
Milky Quartz
Silicon Dioxide (SiO2)
Quartz
Silicon Dioxide (SiO2)
White Quartz Pebble
Silicon Dioxide (SiO2)
Pyrite (Fool's Gold)
Iron Sulfide (FeS2)
Pyrite
Iron Sulfide (FeS2)
Quartz
Quartz (SiO₂)
Green Opal
Hydrated Silica (SiO2·nH2O)
Basalt (Vesicular)
Basalt (Mafic Extrusive Igneous Rock)
Basalt
Basalt (dominated by plagioclase feldspar and pyroxene minerals)
Basalt with Weathered Rind
Basalt (Aphanitic Mafic Igneous Rock)
Basalt (River or Beach Pebble)
Basalt (Mafic Extrusive Igneous Rock)
Basalt
Basalt (Mafic Extrusive Igneous Rock)
Basalt (Road Aggregate)
Basalt (Aphanitic Mafic Igneous Rock)
Diorite (or salt-and-pepper granite pebble)
Phaneritic Igneous Rock (Intermediate Composition)
Pyrite
Pyrite (Iron Disulfide), FeS2
Clear Quartz
Quartz (Silicon Dioxide, SiO2)
Scoria (Vesicular Basalt)
Vesicular Basalt
Basalt
Mafic Igneous Rock (composed primarily of Pyroxene and Plagioclase Feldspar)
Basalt
Extrusive Mafic Igneous Rock (composed primarily of Plagioclase and Pyroxene)
Clear Quartz
Silicon Dioxide (SiO2)