Basalt
Basalt
Category
Browse mineral like byproduct (often mistaken for igneous rock or meteorite) specimens identified by the Rock Identifier community.
Basalt
Basalt
Milky Quartz
Silicon Dioxide (SiO2)
Azurite and Malachite on Matrix
Azurite: Cu3(CO3)2(OH)2; Malachite: Cu2CO3(OH)2
Greenstone
Chlorite schist / Meta-basalt
Green Moss Agate
Silicon Dioxide (SiO2) with inclusions of hornblende or chlorite
Graphite Schist
C (Carbonaceous Schist)
Milky Quartz
Silicon Dioxide (SiO2)
Conglomerate
Conglomerate (clastic sedimentary rock)
Quartz (Common or Milky Quartz)
Silicon Dioxide (SiO2)
Red Quartzite
Quartzite (SiO2 with iron oxide impurities)
Amethyst (Geode)
Silicon Dioxide with Iron impurities (SiO2)
Basalt
Basalt (Mafic volcanic rock)
Pumice
Pumice (Highly vesicular volcanic glass)
Serpentine
Serpentinite (a rock composed primarily of serpentine minerals like antigorite, chrysotile, and lizardite; general formula (Mg, Fe)3Si2O5(OH)4)
Basalt
Basalt
Red Sandstone
Arenite (with Iron Oxide)
Jasper (Iron-stained Chert)
Silicon Dioxide (SiO2)
Chrysocolla
Hydrated copper phyllosilicate, Cu2-xAlx(H2-xSi2O5)(OH)4·n(H2O)
Chalcedony Geode
Chalcedony (SiO2) within a geode structure
Crazy Lace Agate
Silicon Dioxide (SiO2) with impurities
Sandstone with Liesegang Rings
Arenite with Iron Oxide Liesegang Banding
Emerald in Host Rock
Beryl (Be3Al2Si6O18) containing Chromium and/or Vanadium
River Cobble (likely Sandstone or Siltstone type)
Sandstone or Siltstone (common rock types that form river cobbles)
Quartz (Milky or Citrine-tinted)
Silicon Dioxide (SiO2)
Moss Agate
Moss Agate (a variety of Chalcedony, SiO ₂)
Rhyolite
Rhyolite (Extrusive Igneous Rock)
Yellow Quartz / Quartzite Pebble
Silicon Dioxide (SiO2)
Sandstone Beach Pebble
Clastic Sandstone (SiO2 - Quartz-dominant)
Lapis Lazuli
Lapis Lazuli (a rock composed primarily of Lazurite, Sodalite, Calcite, and Pyrite)
Green Aventurine and Clear Quartz
Green Aventurine (Silicon Dioxide - SiO2 with Fuchsite inclusions); Clear Quartz (Silicon Dioxide - SiO2)
Basalt
Basalt
Amethyst
Amethyst (Silicon Dioxide, SiO2)
Mica Schist
Mica Schist (predominantly composed of Muscovite or Biotite silicates)
Quartz (Milky or Rough Quartz)
Silicon Dioxide (SiO2)
River Rocks (Black)
Various lithologies (e.g., basalt, chert, obsidian for black varieties), mechanically rounded clasts
Quartz with Iron Staining
Silicon Dioxide (SiO2)
Gneiss
Gneiss (High-grade metamorphic rock)
Sandstone
Arenite (primarily SiO2, silica)
Granite
Granite (a common name for a felsic intrusive igneous rock)
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
Granite
Granite (Phaneritic intrusive igneous rock)
Granite Cobble
Granite (Phaneritic igneous rock composed of Quartz, Feldspar, and Mica)