Biotite on Quartz Matrix
Biotite - K(Mg,Fe)3(AlSi3O10)(OH,F)2 with Quartz (SiO2)
Category
Browse mineral (biogenic) specimens identified by the Rock Identifier community.
Biotite on Quartz Matrix
Biotite - K(Mg,Fe)3(AlSi3O10)(OH,F)2 with Quartz (SiO2)
Amethyst
Silicon Dioxide (SiO2) with iron impurities
Amethyst
Silicon Dioxide (SiO2) with iron impurities
Amethyst
SiO2 (Silicon Dioxide with iron impurities)
Boulder Opal
Hydrated Silica (SiO2·nH2O)
Quartz (Clear / Rock Crystal)
Silicon Dioxide (SiO2)
Sunstone (Oregon Sunstone)
Labradorite (Feldspar variety) - (Ca, Na)(Al, Si)4O8
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
Moonstone
Orthoclase (Potassium Aluminum Silicate, KAlSi3O8) with inclusions of Albite
Botryoidal Chalcedony (likely Chert or Agatized Coral)
Silicon Dioxide (SiO2)
Amazonite
Amazonite (KAlSi3O8)
Amazonite
Potassium Aluminum Silicate (KAlSi3O8)
Amazonite
Amazonite (KAlSi3O8)
Amethyst
Quartz (Silicon Dioxide with iron impurities), SiO2
Rough Tanzanite
Zoisite (Ca2Al3(SiO4)3(OH))
Citrine (Heat-treated or Natural Quartz)
Silicon Dioxide (SiO2)
Quartz (Citrine or Smoky variant)
Silicon Dioxide (SiO2)
Citrine
Quartz (Silicon Dioxide - SiO2)
Chrysocolla in Quartz (Gem Silica)
Cu2-xAlx(H2-xSi2O5)(OH)4·nH2O (Chrysocolla) / SiO2 (Quartz)
Ferruginous Quartz
Silicon Dioxide (SiO2) with Iron Oxide (Fe2O3) inclusions
Limonite Pseudomorph after Pyrite
Goethite/Limonite FeO(OH)·nH2O replacing Pyrite FeS2
Rose Quartz
Silicon Dioxide (SiO2) with traces of titanium, iron, or manganese
Oceanside Agate (Orbicular Agate)
Silicon Dioxide (SiO2) - Variety of Chalcedony
Quartz (Clear/White)
Silicon Dioxide (SiO2)
Quartz
Silicon Dioxide (SiO2)
Milky Quartz
Silicon Dioxide (SiO2)
Banded Agate (Chert/Chaldcedony)
Silicon Dioxide (SiO₂)
Chalcedony on Matrix
Silicon Dioxide (SiO2)
Amethyst
Amethyst (SiO2 with iron impurities)
Amazonite
Microcline (KAlSi3O8)
Amazonite
Microcline (KAlSi3O8) with lead impurities
Amazonite
Potassium aluminum silicate (Microcline); KAlSi3O8
Amethyst
Silicon Dioxide (SiO2) with iron impurities
Amazonite
K(AlSi3O8) - Microcline variant
Ruby Zoisite
Anyolite (Composition of Green Zoisite, Black Tschermakite, and Red Corundum)
Quartz (Milky or Cloudy Quartz)
Silicon Dioxide (SiO2)
Amazonite
Microcline (KAlSi3O8)
Amethyst (Rose de France)
Silicon Dioxide (SiO2) with iron impurities
Amethyst
Amethyst (Silicon Dioxide, SiO2)
Prehnite
Prehnite - Ca2Al(AlSi3O10)(OH)2
Thunderegg (specifically a Jasper/Agate-filled Geode nodule)
Silicon Dioxide (SiO2) within Rhyolitic Matrix
Sodalite
Na8(Al6Si6O24)Cl2