Basalt River Pebble
Basalt (Mafic Extrusive Volcanic Rock)
Category
Browse mineral on igneous rock specimens identified by the Rock Identifier community.
Basalt River Pebble
Basalt (Mafic Extrusive Volcanic Rock)
Pumice
Vesicular volcanic glass (Amorphous silica mixed with various oxides)
Pumice
Pumice (a highly vesicular volcanic glass)
Pumice
Pumice (a highly vesicular volcanic rock)
Pumice
Vesicular Rhyolite or Dacite Pumice (Amorphous volcanic glass)
Basalt
Mafic volcanic rock (Silicon dioxide 45-52%)
Granite
Phaneritic plutonic rock (SiO2 range 70-75%)
Plagioclase Feldspar (specifically Albite/Oligoclase)
(Na,Ca)(Si,Al)4O8
Fulonite (Fulgurite-like)
Fulgurite (SiO2 fused silica/lechatelierite)
Sodalite
Sodalite - Sodium Aluminum Silicate Chloride (Na8(Al6Si6O24)Cl2)
Calcite on Limestone (or Fossil)
Calcium Carbonate (CaCO3)
Orange Calcite
Calcium Carbonate (CaCO3)
Green Calcite
Calcium Carbonate (CaCO3)
Hematite
Hematite (Iron(III) oxide, Fe2O3)
Blue Chalcedony
Silicon Dioxide (SiO2)
Pyrite (Fool's Gold)
Iron Sulfide (FeS2)
Quartz-Veined Mudstone
Argillaceous Mudstone with Quartz Veining
Pink Granite
Phaneritic Quartz-Feldspar Plutonic Rock
Rhyolite
Rhyolite (High-silica volcanic rock)
Granodiorite
Granodiorite (Intermediate to Felsic Intrusive Rock)
Basalt Arrowhead (worked stone)
Aphanitic mafic volcanic rock (Basalt)
Basalt River Cobble
Basalt (Aphanitic Mafic Volcanic Rock)
Porphyritic Andesite
Porphyritic Andesite (Intermediate Volcanic Rock)
Pink Granite
Phaneritic Plutonic Felsic Rock (Granite)
Basalt (Porphyritic Basalt)
Porphyritic Basalt (Mafic volcanic rock)
Andesite Porphyry
Porphyritic Andesite (Intermediate volcanic rock)
Andesite
Andesite (Intermediate Extrusive Volcanic Rock)
Scoria (Lava Rock)
Scoria (Vesicular Basaltic Glass/Rock)
Gabbro
Gabbro (phaneritic mafic intrusive rock)
Andesite
Andesite (Intermediate Extrusive Volcanic Rock)
Porphyritic Basalt (Flowerstone)
Porphyritic Basalt (Mafic volcanic rock)
Pink Granite
Granite (Phaneritic Quartz-Feldspar rock)
Red Garnet (likely Almandine or Pyrope)
Garnet group: X3Y2(SiO4)3 (e.g., Almandine: Fe3Al2Si3O12)
Bauxite
Bauxite (Al2O3·nH2O)
Lapis Lazuli
Lapis Lazuli (A metamorphic rock primarily composed of Lazurite: (Na,Ca)8(AlSiO4)6(S,Cl,SO4,OH)2)
Lapis Lazuli (Tumbled)
Lazurite-dominated contact metamorphic rock
Sandstone
Sandstone (Sedimentary rock composed of silicate grains)
Granite
Granite (phaneritic intrusive igneous rock consisting mainly of quartz, alkali feldspar, and plagioclase)
Ferruginous Sandstone (Ironstone)
Arenite with Limonite/Goethite cement
Sandstone
Arenite (composed mainly of SiO2)
Sandstone
Arenite (SiO2 predominantly)
Sandstone (with Iron concretions/staining)
Arenite (composed primarily of Quartz and Feldspar with Iron Oxide cement)