Basalt
Basalt (Aphanitic Mafic Igneous Rock)
Category
Browse mineral based alloy (anthropogenic) specimens identified by the Rock Identifier community.
Basalt
Basalt (Aphanitic Mafic Igneous Rock)
Dendritic Limestone
Calcite with Manganese Oxide (Manganese Dendrites)
Sandstone (Micaceous Sandstone)
Arenite (SiO2 with KAl2(AlSi3O10)(OH)2 inclusions)
Basalt with Quartz Vein
Basalt (SiO2 vein inclusion)
Chert (Jasper or Flint variant)
Chert (composed of microcrystalline quartz, SiO2)
Chert (specifically Tan Chert)
Chert (SiO2)
Opalite
Synthetic Glass, SiO2 base with metallic inclusions
Basalt with Quartz/Calcite Veins
Amygdaloidal Basalt (SiO2 or CaCO3 inclusions)
Granite (specifically Pink Granite)
Phaneritic Plutonic Rock (High Potassium Feldspar Granite)
Brecciated Chert
Brecciated Chert (Microcrystalline Quartz, SiO2)
Granodiorite
Granodiorite (phaneritic intrusive igneous rock)
Scoria (with Iron Oxidation)
Vesicular Basalt / Scoria
River Cobble (likely Basalt or Rhyolite)
Extrusive Igneous Rock (Mafic or Intermediate)
Shale
Clastic sedimentary rock (primarily clay and silt minerals)
Quartzite
Quartzite (primarily composed of SiO O₂)
Basalt
Basalt (Mafic volcanic rock)
Fluorite
Fluorite (Calcium Fluoride, CaF2)
Diorite
Intrusive Igneous Rock (Intermediate Composition)
Diorite
Diorite
Granodiorite
Granodiorite (Phaneritic intrusive igneous rock containing Plagioclase, Quartz, and Biotite/Amphibole)
Diorite (Salt and Pepper Rock)
Diorite
Tree Agate
Silicon Dioxide (SiO2) with Chlorite inclusions
Fuchsite
Chromium-rich Muscovite (K(Al,Cr)2(AlSi3O10)(OH)2)
Puddingstone (specifically Gowganda Tillite or St. Joseph Island Puddingstone)
Jasper Conglomerate
Basalt
Extrusive Mafic Igneous Rock
Gneiss
Foliated Metamorphic Rock (Gneiss)
Basalt
Mafic Igneous Rock (primarily Plagioclase Feldspar and Pyroxene)
Sandstone (Iron-stained)
Arenite (composed primarily of SiO2 with Fe2O3 staining)
Basalt
Basalt
Vesicular Basalt
Extrusive mafic igneous rock; primarily (Ca,Na)(Mg,Fe,Al,Si)2O6 (Pyroxene) and (Ca,Na)Al(Al,Si)Si2O8 (Plagioclase Feldspar)
Diorite (Salt and Pepper Rock)
Diorite
Mica Schist
Mica Schist (primarily Muscovite and/or Biotite composition)
Muscovite Mica
Muscovite (Potassium Mica) KAl2(AlSi3O10)(OH)2
Soapstone / Steatite
Steatite (primarily Talc, Mg3Si4O10(OH)2)
Basalt
Basalt (Mafic Extrusive Igneous Rock)
Moss Agate
Silicon Dioxide with inclusions (SiO2 + impurities)
Basalt with Vesicular Texture (Beach Cobble)
Vesicular Basalt (Aphanitic Igneous Rock)
Granite
Granite (Phaneritic intrusive igneous rock)
Ferruginous Sandstone (Grit)
Clastic Sedimentary (Ironstone-rich Sandstone)
Basalt
Basalt (Mafic Extrusive Igneous Rock)
Mica Schist
Mica Schist (Quartz-Biotit-Muscovite Schist)
Biotite Schist
Biotite Schist