Basalt (Weathered Pebble)
Extrusive mafic igneous rock; minerals primarily Plagioclase feldspar and Pyroxene
Category
Browse igneous and mineral specimens identified by the Rock Identifier community.
Basalt (Weathered Pebble)
Extrusive mafic igneous rock; minerals primarily Plagioclase feldspar and Pyroxene
Peridot
Olivine (Magnesium Iron Silicate), (Mg, Fe)2SiO4
Quartz Geode (with possible Manganese or Goethite coating)
Silicon Dioxide (SiO2)
Lepidolite
Lepidolite (K(Li,Al)3(Al,Si,Rb)4O10(F,OH)2)
Man-made Green Quartz (Lab-grown or Treated)
Silicon Dioxide (SiO2) with artificial coloration
Obsidian and Phantom Quartz
Volcanic Glass (SiO2 + MgO + Fe3O4) and Crystalline Quartz (SiO2)
Black Obsidian and Hematite
Volcanic Glass (SiO2) and Hematite (Fe2O3)
Quartz with Mica/Chlorite inclusions
Silicon Dioxide (SiO2) with phyllosilicate inclusions
Jasper (specifically Polychrome or Desert Jasper)
Silicon Dioxide (SiO2) with impurities
Quartz Vein in Gneiss or Basalt
Milky Quartz (SiO2) within Metamorphic Host Rock
Citrine
Crystalline Quartz (SiO2) with iron impurities
Peach Moonstone
Orthoclase Feldspar (KAlSi3O8)
Moonstone
Orthoclase Feldspar ((K,Na)AlSi3O8)
Amethyst
Amethyst (Silicon Dioxide - SiO2)
Moonstone
Orthoclase/Albite (KAlSi3O8 / NaAlSi3O8) with Adularescence
Pyrite
Iron Sulfide (FeS2)
Citrine (likely Heat-Treated Amethyst)
Silicon Dioxide (SiO2)
Blue Calcite
Calcium Carbonate (CaCO3)
Hypersthene
(Mg,Fe)SiO3 - Enstatite-Ferrosilite series
Calcite
Calcite (CaCO₃, Calcium Carbonate)
Magnetite Sand (Black Sand)
Magnetite (Fe3O4)
Magnetite
Iron(II,III) oxide (Fe3O4)
Granite with Epidote
Granite, containing quartz, feldspar, and epidote
Magnetite
Magnetite (Fe3O4)
Blue Apatite
Fluorapatite (Ca5(PO4)3F)
Blue Apatite
Apatite (Group), Ca5(PO4)3(F,Cl,OH)
Blue Apatite
Fluorapatite (Ca5(PO4)3F)
Magnetite (Iron Ore)
Magnetite (Fe3O4)
Pyrite
Iron Sulfide (FeS2)
Magnetite (Iron Ore)
Magnetite (Fe3O4)
Magnetite / Iron Ore
Magnetite (Fe3O4)
Blue Apatite
Fluorapatite (Ca5(PO4)3F)
Magnetite / Hematite mix (Iron Ore)
Fe3O4 (Magnetite) / Fe2O3 (Hematite)
Magnetite Orthorthotropic Rock
Magnetite (Fe3O4)
Sodalite
Sodalite - Na8(Al6Si6O24)Cl2
Magnetite
Magnetite (Fe3O4)
White Topaz
Al2SiO4(F,OH)2
Quartz (Milky/Common Quartz)
Silicon Dioxide (SiO2)
Olivine (Peridot)
Magnesium Iron Silicate (Mg,Fe)2SiO4
Dark Igneous Rock (Likely Basalt or Diabase)
Basalt (extrusive igneous rock) or Diabase (intrusive igneous rock - also known as Dolerite), largely composed of plagioclase feldspar, pyroxene (augite), and sometimes olivine and amphibole. Exact mineralogy would require thin section analysis.
Hypersthene (or Enstatite/Ferrosilite)
Orthopyroxene series (Mg,Fe)SiO3 - specifically, historically hypersthene (intermediate member) now referred to as Enstatite (Mg-rich) or Ferrosilite (Fe-rich)
Amygdaloidal Basalt
Vesicular-Amygdaloidal Basalt (Mafic Extrusive)