Basalt River Pebble
Basalt (fine-grained mafic igneous rock)
Category
Browse sedimentary (volcanic) specimens identified by the Rock Identifier community.
Basalt River Pebble
Basalt (fine-grained mafic igneous rock)
Basalt (Beach Pebble)
Extrusive mafic igneous rock
Basalt
Extrusive mafic igneous rock
Gold in Matrix
Native Gold (Au)
Basalt (Gravel Pebble)
Basalt (contains pyroxene, plagioclase feldspar, and olivine)
Porphyritic Rhyolite (Birdseye Rhyolite)
Rhyolite (Porphyritic texture)
Basalt
Extrusive mafic igneous rock
Basalt
Basalt
Basalt
Basalt (Mafic Extrusive)
Ferrous Slag (Iron Smelting By-product)
Fused Siliceous Slag
Wonderstone
Banded Rhyolite (SiO2 with impurities)
Basalt
Mafic Volcanic Rock (Primarily Plagioclase Feldspar and Pyroxene)
Scoria (Lava Rock)
Scoria (Vesicular Basalt)
Obsidian
Obsidian (principally SiO2 - Silicon Dioxide)
Amygdaloidal Rhyolite (often called Lake Superior Agate relative)
Rhyolite with Calcite/Quartz amygdules (SiO2 and secondary minerals)
Olivine in Basalt matrix
Olivine (Magnesium Iron Silicate - (Mg, Fe)2SiO4)
Native Gold Nugget
Native Gold (Au)
Diorite
Diorite
Diamond (in jewelry)
Carbon (C)
Green Aventurine
Silicon Dioxide (SiO2) with Fuchsite inclusions
Aquamarine with Ruby Accent
Beryllium Aluminum Silicate (Be3Al2Si6O18) with Aluminum Oxide (Al2O3)
Turquoise
Hydrated phosphate of copper and aluminium (CuAl6(PO4)4(OH)8·4H2O)
Olivine (Peridot)
Magnesium Iron Silicate (Mg, Fe)2SiO4
Peridot (Olivine)
Olivine ((Mg, Fe)2SiO4)
Banded Agate
Silicon Dioxide (SiO2)
Tektite (Indochinite)
Tektite (Silica-rich natural glass)
Greenschist
Greenschist (comprising Actinolite, Chlorite, and Epidote)
Basalt
Basalt
Green Apophyllite on Stilbite
Fluorapophyllite-(K) [(KCa4Si8O20F)·8H2O] and Stilbite [NaCa4(Si27Al9)O72·28H2O]
Slag Glass
Glassy Silicate Residue
Tektite (Indochinite)
Tektite (High-silica natural glass)
Granite porphyry
Porphyritic Granite
Mahogany Obsidian
Volcanic glass containing Hematite or Magnetite (SiO2 + Fe2O3)
Obsidian
Volcanic Glass (Primary composition: SiO2 - Silicon Dioxide)
Snowflake Obsidian
Spherulitic Volcanic Glass (SiO2 + impurities)
Basalt
Basalt (Aphanitic Mafic Igneous Rock)
Mahogany Obsidian
Volcanic Glass with Hematite/Magnetite (SiO2 + Fe2O3)
Rhyolite
Rhyolite
Mahogany Obsidian
Volcanic glass (SiO2 with Hematite or Magnetite inclusions)
Olivine Peridotite
Peridotite (comprising Olivine (Mg,Fe)2SiO4 and Pyroxene)
Basalt
Extrusive Mafic Igneous Rock
Basalt
Mafic Igneous Rock (primarily Plagioclase Feldspar and Pyroxene)