Stromatolite
Biogenic Sedimentary Rock (Lithified microbial mat)
Category
Browse not a rock (man made polymer) specimens identified by the Rock Identifier community.
Stromatolite
Biogenic Sedimentary Rock (Lithified microbial mat)
Granite
Phaneritic Igneous Rock (primarily Quartz, Feldspar, and Mica)
Smoky Quartz
Silicon Dioxide (SiO2)
Basalt with Quartz Veins
Amygdaloidal Basalt (matrix) with Crystalline SiO2 (veins)
Petoskey Stone
Hexagonaria percarinata (Fossilized Rugose Coral)
Snowflake Obsidian (or similar porphyritic volcanic rock)
Obsidian with Spherulites (if glassy), or Porphyritic Rhyolite/Andesite (if crystalline groundmass)
Granite
Granite (Felsic Plutonic Rock)
Sandstone (Quartzose)
Arenite (primarily SiO2)
Garnet Schist or Garnet-bearing Quartzite
Metamorphic rock containing Almandine Garnet (Fe3Al2(SiO4)3) and Quartz (SiO2)
Chert (Quartz Variety)
Chert (mostly SiO2 / Silicon Dioxide)
Brown Sandstone
Arenite (primarily Quartz and Feldspar, with Iron Oxide cement)
Felsic Igneous Rock (likely Rhyolite or weathered Granite)
Felsic Volcanic/Plutonic Rock
Chert (Nodular)
Microcrystalline Silica (SiO2)
Druzy Quartz (on Quartzite or Chert)
Silicon Dioxide (SiO2)
Turquoise in Matrix
Hydrated phosphate of copper and aluminum (CuAl6(PO4)4(OH)8·4H2O)
Quartz in Matrix (possibly with Biotite or Hornblende)
Quartz (Silicon Dioxide, SiO2) in Granitic Matrix
Limestone
Calcium Carbonate (CaCO3)
Fossilized Brachiopod/Bivalve in Limestone
Brachiopoda or Bivalvia fossil in Calcite/Limestone (CaCO3)
Emerald In Matrix
Beryl (Be3Al2Si6O18) with trace Chromium/Vanadium
Sandstone
Clastic Sedimentary Rock (primarily SiO2)
Porphyritic Basalt (Chinese Writing Stone)
Porphyritic Basalt or Porphyritic Andesite
Sandstone (Ferruginous)
Arenite (primarily SiO2 with Fe2O3 staining)
Arkosic Sandstone
Arkose (Clastic Sedimentary Rock)
Chalcedony
Silicon Dioxide (SiO2)
Eclogite
Eclogite (comprising Omphacite and Garnet)
Limestone
Calcium Carbonate (CaCO3)
Quartzite with Iron Staining
Quartzite (primarily SiO2 with Fe2O3 staining)
Quartzite (Iron-stained)
Quartzite (SiO2 with Fe-oxides)
Granodiorite / Granite
Granodiorite (containing Quartz SiO2, Plagioclase Feldspar, and Biotite)
Limestone (Brecciated/Recrystallized)
Calcium Carbonate (CaCO3)
Scoria
Scoria (a vesicular basalt or andesite)
Granite
Granite (phaneritic felsic intrusive rock)
Basalt
Mafic volcanic rock (consisting mostly of plagioclase, pyroxene, and olivine)
Basalt
Basalt
Basalt (Porphyritic)
Porphyritic Mafic Extrusive (Basalt)
Basalt
Basalt (Mafic Extrusive Igneous Rock)
Granite Pebble
Felsic Intrusive Igneous Rock (composed of Quartz, Alkali Feldspar, and Plagioclase)
Basalt
Mafic Igneous Rock (primarily Plagioclase and Pyroxene)
Basalt
Basalt (Aphanitic Mafic Volcanic Rock)
Basalt
Basalt (Aphanitic Mafic Igneous Rock)
Basalt
Basalt (Aphanitic Mafic Igneous Rock)
Basalt
Extrusive Mafic Igneous Rock (composed primarily of plagioclase feldspar and pyroxene)