Biotite / Black Mica
K(Mg,Fe)3(AlSi3O10)(F,OH)2
Category
Browse mixed (predominantly sedimentary and igneous) specimens identified by the Rock Identifier community.
Biotite / Black Mica
K(Mg,Fe)3(AlSi3O10)(F,OH)2
Smoky Quartz
Smoky Quartz (SiO2)
Orthoclase Feldspar
Orthoclase (KAlSi3O8)
Moonstone
Orthoclase (KAlSi3O8) with inclusions of Albite (NaAlSi3O8)
Sodalite
Sodalite (Na8(Al6Si6O24)Cl2)
Amethyst
Crystalline Silicon Dioxide with Iron impurities (SiO2)
Sodalite
Sodalite (Na8(Al6Si6O24)Cl2)
Lapis Lazuli
Lapis Lazuli (Complex silicate mineral mix including Lazurite, Pyrite, and Calcite)
Sodalite
Sodalite (Sodium Aluminum Silicate Chloride) - Na8(Al6Si6O24)Cl2
River Quartz Cobble
Silicon Dioxide (SiO2)
Citrine Quartz
SiO2 (Silicon Dioxide with Iron impurities)
Labradorite (Gray Tumbled)
Labradorite (Ca,Na)(Al,Si)4O8
Amazonite
K(AlSi3O8)
Blue Sapphire (in a faceted jewelry setting)
Corundum (Al2O3) with trace Iron and Titanium
Muscovite Mica
Muscovite (Potassium Aluminum Silicate) - KAl2(AlSi3O10)(F,OH)2
Rose Quartz
Quartz (Silicon Dioxide, SiO2)
Rose Quartz
SiO2 (Silicon Dioxide with trace amounts of titanium, iron, or manganese)
Smoky Quartz (Faceted Beads)
Silicon Dioxide (SiO2)
Rose Quartz
Silicon Dioxide (SiO2) with trace amounts of titanium, iron, or manganese
Quartz Pebble (Water-worn)
Silicon Dioxide (SiO2)
Amethyst
Silicon Dioxide (SiO2) with iron impurities
Sodalite
Sodalite, Na8(Al6Si6O24)Cl2
Arfvedsonite in Quartz
Arfvedsonite [Na3(Fe2+4Fe3+)Si8O22(OH)2] often hosted in Quartz or Feldspar
Granite
Granite
Olivine (Peridotite)
Olivine Group; (Mg, Fe)2SiO4
Quartz-veined Siltstone
Siltstone with Quartz (SiO2) veins
Obsidian
Volcanic glass (SiO2 - Silicon dioxide predominant composition)
White Quartz (Milky Quartz)
Silicon Dioxide (SiO2)
Rose Quartz
Silicon Dioxide (SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Quartz (Milky Quartz with Iron Staining)
Silicon Dioxide (SiO2)
Greenstone with Epidote or Quartz Vein
Epidiorite or Metabasalt (composed largely of Chlorite, Epidote, and Amphibole)
Pegmatite (Granitic) with Tourmaline
Granitic Pegmatite (containing Schorl and Quartz)
Red Jasper
Silicon Dioxide with Hematite impurities (SiO2 + Fe2O3)
Sedimentary rock with quartz veining
Laminated siltstone or mudstone with hydrothermal quartz veins
Sedimentary Sandstone (Sandstone Slab)
Arenite (SiO2 with Fe2O3 staining)
Fossil Shell in Sedimentary Matrix
Bivalvia (fossil) in Calcium Carbonate Matrix
Fossilized Fish (Lepidotes)
Lepidotes sp. (Order: Lepisosteiformes)
Chalk / Sedimentary Limestone
Calcium Carbonate (CaCO3) - Biogenic Sedimentary Rock
Chalk (Sedimentary Limestone)
Calcium Carbonate (CaCO3) - Bioclastic Limestone
Sandstone
Arenite (primarily SiO2)
Fossilized Bivalve Shell
Bivalvia (fossil specimen)