Basalt
Basalt (Aphanitic extrusive igneous rock)
Category
Browse metamorphic rock (composed of multiple minerals) specimens identified by the Rock Identifier community.
Basalt
Basalt (Aphanitic extrusive igneous rock)
Quartz with mica and feldspar (Pegmatite fragment)
Granitic Pegmatite (composed mainly of SiO2 with KAlSi3O8)
Caliche (also known as hardpan, calcrete, kankar)
Primarily composed of calcium carbonate (CaCO₃), often mixed with other minerals like quartz, clay minerals, and iron oxides.
Sandstone (Ferruginous)
Arenite with Iron Oxide cement (SiO2 + Fe2O3)
Granite
Granite (Felsic Plutonic Rock)
Banded Gneiss
Gneiss (pronounced "nice")
Petrified Wood
Silicified Wood (primarily SiO2 - Silicon Dioxide / Chalcedony)
Muscovite Mica
Muscovite / KAl2(AlSi3O10)(OH)2
Shale with Vein Infillings
Shale (a fine-grained clastic sedimentary rock). The veins could be Calcite (CaCO3), Quartz (SiO2), or other minerals.
Quartz
Quartz (SiO2 - Silicon Dioxide)
Banded Jasper (possibly "Picture Jasper")
Jasper (a microcrystalline variety of Quartz / Silicon Dioxide - SiO2)
Greenschist / Migmatite
Regional Metamorphic Complex (Facies: Greenschist to Amphibolite)
Granite
Granite (a common rock type, not a single mineral with a formula. Composed primarily of quartz, feldspar, and mica/amphibole).
Pink Granite
Granite (Phaneritic igneous rock)
Quartz (likely tumbled or naturally water-worn)
Quartz (SiO₂ - Silicon Dioxide)
Conglomerate
Conglomerate (Rock composed predominantly of rounded clasts > 2mm)
Coquina / Fossiliferous Limestone
Calcite-rich Bioclastic Sedimentary Rock (CaCO3)
Red Siltstone
Siltstone (composed mainly of SiO2 and Fe2O3)
Granite
Phaneritic Intrusive Igneous Rock (composed primarily of Quartz, Feldspar, and Mica)
Eclogite
Eclogite (Omphacite + Pyrope)
Blue Apatite
Apatite (Group), Ca5(PO4)3(F,Cl,OH)
Magnetite (Small Granule)
Magnetite (Fe3O4)
Dalmatian Stone
Dalmatian Jasper (Aplitic Perthite)
Drill Core Samples (Varied Lithology)
Multi-lithological core samples (containing potential granite, marble, and phyllite/schist sequence)
Lapis Lazuli
Na6Ca2(Al6Si6O24)(S,SO4,Cl)1-2 (primarily containing Lazurite with inclusions of Calcite and Pyrite)
Agate
Agate (Silicon Dioxide, SiO2)
Note: Image shows a biological specimen (Rat), not a rock. Representative geological equivalent: Galena (due to lead-grey colors in fur).
Galena (PbS)
Clear Quartz (or Rock Crystal)
Quartz (SiO₂)
Lapis Lazuli
Lapis lazuli (a rock primarily composed of Lazurite, (Na,Ca)8(AlSiO4)6(S,Cl,SO4,OH)2)
Quartz
Quartz (SiO2 - Silicon Dioxide)
Serpentine
Serpentine Group Minerals (e.g., Antigorite, Chrysotile, Lizardite)
Coquina / Shelly Limestone
Bioclastic Limestone (composed of CaCO3)
Sandstone
Arenite
Siltstone
Siltstone (primarily composed of SiO2 with various clay minerals)
Green Aventurine
Silicon Dioxide (SiO2) with inclusions of Fuchsite (K(Al,Cr)2(AlSi3O10)(OH)2)
Oolitic Chert
Silicon Dioxide (SiO2) with oolitic texture
Quartz
Quartz (SiO₂)
Granite
Phaneritic Igneous Rock (composed primarily of Quartz SiO2, Alkali Feldspar, and Plagioclase)
Granite
Intrusive Igneous Rock (composed of Quartz, Alkali Feldspar, and Plagioclase)
Labradorite (likely Black Labradorite or Larvikite)
Labradorite (Na,Ca)(Al,Si)4O8. If a rock, it is typically anorthosite, gabbro, or norite, or a variety of syenite called Larvikite if it is specifically from Larvik, Norway.
Indigo Gabbro
Gabbro (composed of plagioclase feldspar, pyroxene, and olivine)
Calcite
Calcite (CaCO₃, Calcium Carbonate)