Plagioclase Feldspar
NaAlSi3O8 – CaAlSi2O8 (Sodium-Calcium Aluminum Silicates)
mineral
Category
Mineral (Silicate Replaced Organic Material)
Browse mineral (silicate replaced organic material) specimens identified by the Rock Identifier community.
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Chrysoprase (Nickel-bearing Chalcedony)
Silicon Dioxide (SiO2) with traces of Hydrous Nickel Silicates
mineral
Granite Pegmatite with Muscovite Mica
Granite Pegmatite (Silicon Dioxide and complex silicates)
igneous
Fossilized Shark Tooth
Elasmobranchii (Class) fossil
fossil
Jasper (specifically Chert or Orbicular Jasper)
Silicon Dioxide (SiO2)
sedimentary
Olivine (Peridotite)
(Mg,Fe)2SiO4 (Magnesium Iron Silicate)
igneous
Chert (specifically Blue Chert or Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Chalcedony (Chert/Flint variety)
Silicon Dioxide (SiO2)
sedimentary
Chert (specifically Flint)
Chert (SiO2)
sedimentary
White Marble
Recrystallized Calcite Rock (CaCO3)
metamorphic
Variscite (or potentially a turquoise/variscite matrix cabochon, or an impression jasper)
AlPO4·2H2O (Variscite) or related phosphate/silicate material depending on exact composition
Mineral
Chert (Chert Nodule with Cortex)
Microcrystalline Quartz (SiO2)
sedimentary
Chert (Jasper/Flint variety)
Microcrystalline quartz (SiO2)
sedimentary
Chert (specifically Flint or Common Chert node)
Silicon Dioxide (SiO2)
sedimentary
Chert Nodule (Flint)
Silicon Dioxide (SiO2)
sedimentary
Chert (or Jasper)
Microcrystalline Quartz (SiO2)
sedimentary
Chert (and Flint variant)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Sandstone (Ferruginous)
Arenite with Iron-Oxide Cement
sedimentary
Moss Agate / Carnelian Agate
Silicon Dioxide (SiO2) with iron and manganese inclusions
mineral
Jasper with Quartz Vein
Silicon Dioxide (SiO2) with impurities
sedimentary
Vesuvianite (Idocrase)
Ca19(Al, Mg, Fe)13(SiO4)10(Si2O7)4(OH, F, O)10
mineral
Aquamarine
Aquamarine (Beryl variety) - Be3Al2(Si6O18)
mineral
Travertine
Calcareous Tufa / Travertine (CaCO3)
sedimentary
Chert (and/or Flint)
Microcrystalline Quartz (SiO2)
sedimentary
Epidote with Feldspar/Quartz (Unakite-like)
Epidotized Granite (Ca2(Al,Fe)3(SiO4)3(OH) + KAlSi3O8)
metamorphic
Red Jasper
Jasper (Silicate mineral - SiO2)
sedimentary
Jasper
Jasper (Silicate mineral, SiO2)
sedimentary
Chert (River Pebble)
Microcrystalline Quartz (SiO2)
sedimentary
Shale
Fissile Clay-dominant Mudrock (SiO2, Al2O3, K2O, Na2O, CaO, MgO)
sedimentary
Chert (Basanite / Jasperoid)
Microcrystalline Quartz (SiO2)
sedimentary
Chert (Jasper/Agate variety)
Microcrystalline Quartz (SiO2)
sedimentary
Glauconitic Sandstone (or Greenstone)
Glauconitic Sandstone with Quartz
sedimentary
Mother of Pearl and Onyx
Aragonite (Mother of Pearl) and Chalcedony (Onyx)
mineral
Water and Silt (Sedimentary Environment)
Suspended Sediment / H2O (dihydrogen monoxide)
sedimentary
Quartz Pebble
Silicon Dioxide (SiO2)
mineral
Chert (Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Chert (variously known as Flint)
Silicon Dioxide (SiO2)
sedimentary
Moss Agate
Silicon Dioxide (SiO2) with mineral inclusions of hornblende or chlorite
Mineral (variety of Chalcedony)
Mica Schist
Mica Schist (predominantly Muscovite or Biotite sheet silicates)
metamorphic
Unakite
Epidotized Granite
metamorphic
Coquina / Limonite-stained Limestone
Sedimentary Limestone with Iron Oxyhydroxide (FeO(OH)·nH2O)
sedimentary
Limonite after Marcasite (Propeller Conchoid)
Goethite/Limonite pseudomorph after Marcasite (FeO(OH)·nH2O)
mineral