Basalt
Basalt (composition predominately Plagioclase feldspar and Pyroxene)
Category
Browse metamorphic rock (formed from a fibrous crocidolite asbestos) specimens identified by the Rock Identifier community.
Basalt
Basalt (composition predominately Plagioclase feldspar and Pyroxene)
Chert (Iron-Stained)
Microcrystalline Silica (SiO2)
Pink Rhodonite
Manganese Silicate (MnSiO3)
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
Rhodonite
Manganese Silicate (Mn,Fe,Mg,Ca)SiO3
Sodalite
Sodalite (Na8(Al6Si6O24)Cl2)
Chert / Chalcedony (likely carnelian or flint variety)
Silicon Dioxide (SiO2)
Rhodonite
Rhodonite (Manganese Iron Magnesium Calcium Silicate) - (Mn,Fe,Mg,Ca)SiO3
Green Aventurine
Silicon Dioxide (SiO2) with Fuchsite inclusions
Banded Gneiss
Gneiss (High-grade metamorphic rock typically composed of Quartz, Feldspar, and Biotite/Amphiboles)
Anthracite Coal
Anthracite (Carbon-based metamorphic rock, 86-97% C)
Quartz
Silicon Dioxide (SiO2)
Slate
Foliated Metamorphic Rock (composed mainly of Quartz, Illite, and Chlorite)
Granite Gneiss
High-grade regional metamorphic rock (Quartz-Feldspar Gneiss)
River Pebbles and Quartz
Mixed Igneous, Sedimentary, and Metamorphic Rocks (Silicon Dioxide SiO2 dominant)
Raw Emerald in Schist Matrix
Beryl (Be3Al2Si6O18) in Mica Schist
Shale or Slaty Mudstone
Argillaceous sedimentary rock
Green Aventurine
Silicon Dioxide (SiO2) with Chromium-rich Fuchsite mica
River Rock / Stream Pebble
Fluvial Clast / Rounded Sedimentary Particle
Granodiorite
Granodiorite (containing Plagioclase, Quartz, and Biotite)
Yellow Quartzite (River Pebble)
Crystalline Quartz (SiO2)
Amethyst
Amethyst (Silicon Dioxide, SiO2)
Basalt
Basalt (Aphanitic-fine grained mafic igneous rock)
Basalt
Basalt (Mafic Extrusive)
Ferrous Slag (Iron Smelting By-product)
Fused Siliceous Slag
River Cobble (Gneiss/Migmatite)
Gneissic Metamorphic Rock (composed mainly of Quartz, Feldspar, and Biotite)
Basalt with Granite Inclusions (Xenoliths)
Mafic igneous rock (Basalt) with Sialic minerals
Smoky Quartz
Silicon Dioxide (SiO2)
Biotite (Mica)
Biotite - K(Mg,Fe)3AlSi3O10(F,OH)2
Clear Quartz Crystal (Herkimer Diamond style)
Silicon Dioxide (SiO2)
Peacock Ore
Bornite (Cu5FeS4)
Slate
Slate (a fine-grained, foliated metamorphic rock). Mineral composition: Primarily composed of mica minerals (muscovite, chlorite, sericite) and quartz, with minor amounts of hematite, pyrite, and other accessory minerals.
Rhodonite
Rhodonite (Manganese Iron Magnesium Calcium Silicate)
Veined Limestone (Micrite) with Quartz/Calcite Veins
Calcium Carbonate (CaCO3) with Silicate or Carbonate inclusions
Jade
Jadeite or Nephrite
Agate (Common Chalcedony)
Silicon Dioxide (SiO2)
Sandstone (Quartzose)
Arenite (primarily SiO2)
Basalt
Extrusive mafic igneous rock
Quartzite with Chlorite
Metamosphosed Quartz Sandstone (SiO2 with (Mg,Fe)3(Si,Al)4O10(OH)2 inclusions)
Druzy Quartz on Chert/Chalcedony
Silicon Dioxide (SiO2)
Quartz Vein Rock
Quartz (Silicon Dioxide, SiO2)
Rhodonite
Rhodonite (MnSiO3)