Prehnite
Prehnite (Ca2Al(AlSi3O10)(OH)2)
mineral
Category
Mineral (Tectosilicate)
Browse mineral (tectosilicate) specimens identified by the Rock Identifier community.
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Milky Quartz
Silicon Dioxide (SiO2)
mineral
Flower Agate (Cherry Blossom Agate)
Chalcedony (SiO2) with Opaque Inclusions
mineral
Red Tiger's Eye
Pseudomorph of Quartz after Crocidolite (SiO2 with Fe2O3 inclusions)
metamorphic
Amazonite
Potassium Feldspar (KAlSi3O8)
mineral
Mookaite Jasper
Silicified Radiolarite (SiO2)
sedimentary
Opal
Hydrated Amorphous Silica (SiO2·nH2O)
Mineral
Amethyst
Silicon Dioxide (SiO2) with iron impurities
mineral
Chalcedony
Chalcedony (SiO2)
mineral
Quartz (Smoky Quartz variant)
Silicon Dioxide (SiO2)
mineral
Strawberry Quartz (Red Aventurine)
Silicon Dioxide (SiO2) with Hematite/Goethite inclusions
mineral
Drill Core (Basalt or Andesite)
Volcanic porphyry (mafic to intermediate)
igneous
White Opal (Common)
Hydrated Silica (SiO2·nH2O)
mineral
Golden Healer Quartz
Silicon Dioxide (SiO2) with limonite/hematite inclusions
mineral
Quartz Vein in Host Rock (likely Sandstone or Mudstone)
Silicon Dioxide (SiO2) within Sedimentary Matrix
sedimentary
Amazonite
Amazonite (KAlSi3O8)
mineral
Rainbow Moonstone with Black Tourmaline
White Labradorite (Feldspar variety, (Na,Ca)(Al,Si)4O8) with Schorl (NaFe3Al6(BO3)3Si6O18(OH)4)
mineral
Anyolite (Ruby in Zoisite)
Zoisite with inclusions of Hornblende and Ruby (Ca2Al3(SiO4)3(OH))
metamorphic
Tourmalinated Quartz
Silicon Dioxide (SiO2) with Schorl inclusions (NaFe2+3Al6(BO3)3Si6O18(OH)4)
mineral
Ethiopian Fire Opal
Hydrated Silica (SiO2·nH2O)
mineral
Chlorastrolite (Isle Royale Greenstone)
Chlorastrolite (Pumpellyite-(Mg,Al)), formula: Ca2(Mg,Fe)Al2(SiO4)(Si2O7)(OH)2∙H2O
mineral
Bornite
Copper Iron Sulfide (Cu5FeS4)
mineral
Chalcopyrite (Peacock Ore)
Chalcopyrite (CuFeS2)
mineral
Green Aventurine
Aventurine Quartz (SiO2 + Fuchsite mica)
Mineral
Amygdaloidal Rhyolite
Amygdaloidal felsic extrusive rock
igneous
Magnetite (Iron Ore)
Magnetite (Fe3O4)
mineral
Gneissic Schist
Foliated Metamorphic Rock (Schist/Gneiss transition)
metamorphic
Granite
Phaneritic Igneous Rock (primarily Quartz, Feldspar, and Mica)
igneous
Chrysocolla on Matrix
Hydrated copper phyllosilicate mineral (Cu,Al)2H2Si2O5(OH)4·nH2O
mineral
Chrysocolla in Matrix
Hydrated copper phyllosilicate mineral (Cu,Al)2H2Si2O5(OH)4·nH2O
mineral
Quartz Geode or Druzy Quartz in Host Rock
Silicon Dioxide (SiO2)
mineral
Ferruginous Quartz
Silicon Dioxide (SiO2) with Iron Oxide (Fe2O3) inclusions
mineral
Limonite (Iron Ore)
Limonite (Hydrated Iron Oxide, FeO(OH)·nH2O)
Mineral
Schist (Micaceous Schist)
Mica Schist
metamorphic
Sandstone (Quartzose)
Arenite (primarily SiO2)
sedimentary
Greenschist
Greenschist (Chlorite-actinolite schist)
metamorphic
Magnetite with Pyrite or Chalcopyrite inclusions
Magnetite (Fe3O4) with Pyrite (FeS2)
mineral
Diorite
Intermediate plutonic igneous rock
igneous
Pyrite in Shale
Iron Sulfide (FeS2) in Sedimentary Matrix
mineral
Limonite (Iron Ore)
FeO(OH)·nH2O (Hydrous ferric oxide)
mineral
Shale
Shale (Lutite)
sedimentary
Blue Celestite (with Galena)
Strontium sulfate (SrSO4) and Lead sulfide (PbS)
mineral