Biotite (Mica)
K(Mg,Fe)3AlSi3O10(OH,F)2
Category
Browse mineral_rock specimens identified by the Rock Identifier community.
Biotite (Mica)
K(Mg,Fe)3AlSi3O10(OH,F)2
Limonite/Goethite Gossan
FeO(OH)·nH2O (Hydrated iron oxide)
Citrine
Silicon Dioxide (SiO2)
Milky Quartz Pebble
Quartz (Silicon Dioxide, SiO2)
Jasper
Silicon Dioxide (SiO2)
Parti Sapphire
Corundum (Al2O3)
Rhodonite
Manganese silicate (Mn,Fe,Mg,Ca)SiO3
Aquamarine
Beryl (Be3Al2Si6O18)
Blue Agate (Dyed)
Silicon Dioxide (SiO2) with artificial pigment
Larimar
Pectolite (NaCa2Si3O8(OH))
Quartz Geode in Sedimentary Matrix
Silicon Dioxide (SiO2) within a limestone/dolostone host
Agate (specifically Lake Superior Agate style or Banded Chalcedony)
Silicon Dioxide (SiO2) - Cryptocrystalline Quartz
Banded Agate (specifically Carnelian Agate)
Cryptocrystalline Quartz (SiO2)
Quartz with Iron Staining
Silicon Dioxide (SiO2) with Hematite inclusions
Biotite or Phlogopite Mica
K(Mg,Fe)3(AlSi3O10)(F,OH)2
Quartz Vein in Host Rock
Silicon Dioxide (SiO2) within Metasedimentary or Igneous matrix
Olivine in Basalt matrix
Peridotite (Mg, Fe)2SiO4
Milky Quartz
Silicon Dioxide (SiO2)
Clear Quartz
Quartz (Silicon Dioxide, SiO2)
Amethyst (Polished Point)
Crystalline Quartz (SiO2 with iron impurities)
Gold Nuggest
Native Gold (Au)
Black Onyx
Silicon dioxide (SiO2)
Carnelian
Carnelian (Silica, SiO2)
Agate
Banded Chalcedony (SiO2)
Sodalite
Sodalite (Na8(Al6Si6O24)Cl2)
Petrified Wood
Silicified Wood (primarily SiO2)
Blue Lace Agate
Silicon Dioxide (SiO2)
Rose Quartz
SiO2 (Silicon Dioxide with trace amounts of titanium, iron, or manganese)
Diamond
Carbon (C)
Iceland Spar (Optical Calcite)
Calcite (CaCO3)
Basalt
Basalt (Aphanitic Mafic Igneous Rock)
Granite
Phaneritic Felsic Intrusive Rock (Granite)
Hag Stone
Perforated Sedimentary Rock (typically Limestone or Sandstone)
Mica Schist
Mica Schist (primarily Muscovite or Biotite sheet silicates)
Milky Quartz
Silicon Dioxide (SiO2)
Sandstone (likely Quartzose Sandstone)
Arenite (primarily SiO2)
Sandstone
Arenite (primarily SiO2)
Sandstone
Arenite (primarily SiO2)
Sandstone
Arenite (primarily SiO2)
Basalt with Secondary Mineralization (Likely Zeolites or Calcite)
Aphanitic mafic volcanic rock with secondary mineral inclusions (e.g., CaAl2Si3O10·3H2O for Scolecite)
Quartz / Quartzite
Silicon Dioxide (SiO2)
Biotite Schist
Biotite Schist