Common Opal
Hydrated amorphous silica (SiO2·nH2O)
mineral
Category
Mineralological Specimen
Browse mineralological specimen specimens identified by the Rock Identifier community.
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Jasper
Microcrystalline Quartz (SiO2)
sedimentary
Jasper
Microcrystalline Quartz (SiO2)
sedimentary
Jasper
Microcrystalline Quartz (SiO2)
sedimentary
Fuchsite
K(Al,Cr)2(AlSi3O10)(OH)2
mineral
Chrysocolla in Quartz
Hydrated copper phyllosilicate with silicon dioxide (Cu2-xAlx(H2-xSi2O5)(OH)4·nH2O + SiO2)
mineral
Quartz Vein Rock with Feldspar
Silicon Dioxide (SiO2) with Potassium Feldspar
mineral
Quartz
Silicon Dioxide (SiO2)
mineral
Sandstone (Iron-stained Pebble)
Sandstone (Quartz/Hematite dominated)
sedimentary
Peanut Wood
Petrified Wood (Silicified Araucaria with Teredo boreholes)
fossil
Jasper
Silicon dioxide (SiO2)
sedimentary
Amethyst
Silicon Dioxide (SiO2) containing iron impurities and irradiation
mineral
Emerald in Host Rock
Beryl (Be3Al2Si6O18) with Chromium/Vanadium impurities
mineral
Tiger's Eye
Silicon dioxide with fibrous inclusions (SiO2)
mineral
Green Quartz (Prasiolite/Adventurine)
Silicon Dioxide with inclusions (SiO2)
mineral
Gold-bearing Quartz with Iron Oxides
Quartz (SiO2) with Limonite/Goethite (FeO(OH)) and Pyrite (FeS2)
mineral
Azurite Malachite
Azurite (Cu3(CO3)2(OH)2) and Malachite (Cu2CO3(OH)2)
mineral
Bloodstone
Heliotrope
Mineral
Citrine
Silicon Dioxide (SiO2)
mineral
Mixed Rock and Mineral Collection
Various geological specimens
igneous, sedimentary, and metamorphic
Quartzite Pebble
Quartzite (primarily SiO2)
metamorphic
Sandstone with Mineral Veining or Crust
Sedimentary Sandstone (mostly SiO2 with Fe2O3 tinting)
sedimentary
Quartzite Pebble
Metamorphosed Quartz Sandstone (SiO2)
metamorphic
Quartz Pebble with Muscovite Mica
Quartz (SiO2) with Muscovite Mica (KAl2(AlSi3O10)(F,OH)2)
sedimentary
Schist (Micaceous Schist)
Mica Schist
metamorphic
Pink Granite
Phaneritic Felsic Igneous Rock
igneous
Pyrite
Iron Sulfide (FeS2)
mineral
Chert (Vuggy or Chalcedony)
Cryptocrystalline Quartz (SiO2)
sedimentary
Quartz Druzy in Brecciated Matrix
Silicon Dioxide (SiO2) in Lithic Breccia
sedimentary
Granite
Intrusive Igneous Rock
igneous
White Quartz Pebble
Quartz (Silicon Dioxide, SiO2)
mineral
Unknown Dark Stone
Unknown
igneous
Pumice
Pumice (Volcanic glass / Felsic extrusive rock)
igneous
Quartz Pebble
Silicon Dioxide (SiO2)
sedimentary
Jasper and Quartzite Breccia
Silicified sedimentary breccia
sedimentary
White Quartz Pebble
Silicon Dioxide (SiO2)
mineral
Quartz Pebble (Iron-Stained)
Silicon Dioxide (SiO2)
mineral
Pink-gray granite
Granite; chiefly quartz, alkali feldspar, plagioclase, and biotite/hornblende
igneous
Aventurine Quartz
Silicon Dioxide with Fuchsite inclusions (SiO2 + K(Al,Cr)2AlSi3O10(OH)2)
mineral
Copper Ore (Malachite, Azurite, and Chalcopyrite in Host Rock)
Copper-bearing polymetallic mineral aggregate (Cu-minerals)
mineral
Mica (Biotite and Muscovite) in Matrix
Potassium aluminum silicate with iron/magnesium (KAl2(AlSi3O10)(F,OH)2 / K(Mg,Fe)3AlSi3O10(F,OH)2)
igneous
Toast
Triticum aestivum (processed)
not a geological specimen