Prehnite
Prehnite (Ca2Al2Si3O10(OH)2)
mineral
Category
Organic Gemstone (Often Associated With Sedimentary Sequences)
Browse organic gemstone (often associated with sedimentary sequences) specimens identified by the Rock Identifier community.
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Sodalite
Na8(Al6Si6O24)Cl2
mineral
Rhodonite
Manganese Silicate (Mn,Fe,Mg,Ca)SiO3
mineral
Rhodonite
Manganese Silicate (Mn,Fe,Mg,Ca)SiO3
mineral
Red Jasper
Silicon Dioxide (SiO2)
sedimentary
Petrified Wood
Silicified Wood (primarily SiO2)
metamorphic
Fluorite (specifically Blue John or Banded Fluorite)
Calcium Fluoride (CaF2)
mineral
Fuchsite (Green Muscovite in Quartz)
Chromium-rich Muscovite (K(Al,Cr)2(AlSi3O10)(OH)2)
metamorphic
Pyrite
Iron Sulfide (FeS2)
mineral
Jasper
Silicon Dioxide (SiO2) - Microcrystalline Quartz
sedimentary
Jasper
Microcrystalline Quartz (SiO2)
sedimentary
Pyrite
Iron Sulfide (FeS2)
mineral
Jasper
Microcrystalline Quartz (SiO2)
sedimentary
Leopard Skin Jasper
Silicon Dioxide (SiO2) with impurities
sedimentary
Black Limestone
Bituminous Limestone (Calcium Carbonate - CaCO3)
sedimentary
Chert (Green Fossilized Algae or Jasper)
Silicon Dioxide (SiO2)
sedimentary
Banded Chert
Microcrystalline Quartz (SiO2)
sedimentary
Lepidolite
K(Li,Al)3(Al,Si,Rb)4O10(F,OH)2
mineral
Carnelian
Carnelian (a variety of Chalcedony, SiO ₂)
Mineral (specifically a variety of Chalcedony, which is a cryptocrystalline quartz)
Petrified Wood
Silicified Wood (SiO2)
sedimentary
Pink Tourmaline (Rubellite)
Elbaite (Tourmaline group) - Na(Li,Al)3Al6(BO3)3Si6O18(OH)4
mineral
Amazonite
Microcline (KAlSi3O8) with trace lead (Pb)
mineral
Howlite
Calcium borosilicate hydroxide (Ca2B5SiO9(OH)5)
mineral
Milky Quartz
Silicon Dioxide (SiO2)
mineral
Amber with dark mineral/organic inclusions
Fossilized plant resin (amber; chiefly polymerized diterpenoid resin)
gemstone
Kyanite in Quartz
Kyanite (Al2SiO5) with Quartz (SiO2)
metamorphic
Tumbled carnelian (red-orange chalcedony)
Carnelian, a cryptocrystalline variety of quartz: SiO₂
gemstone
Chert (Flint)
Silicon Dioxide (SiO2)
sedimentary
Petrified Wood
Silicified Wood (SiO2)
fossil
Amber
Succinite (Formula: C10H16O)
Mineraloid
Tiger's Eye (with Hematite/Magnetite matrix)
Pseudomorph of Quartz after Crocidolite (SiO2 with FeOOH/Fe2O3)
metamorphic
Red Jasper
SiO2 (Silicon Dioxide with Iron Oxide inclusions)
sedimentary
Chert (Brown variety / Common Jasper)
Microcrystalline Quartz (SiO2)
sedimentary
Celestine
SrSO4
mineral
Red Jasper
Microcrystalline Quartz (SiO2)
sedimentary
Fluorite
Calcium Fluoride (CaF2)
mineral
Polychrome Jasper
Microcrystalline Quartz (SiO2)
sedimentary
Fluorite
Fluorite (Calcium Fluoride, CaF2)
mineral
Green Jasper
Silicon Dioxide (SiO2) with mineral inclusions
sedimentary
Lepidolite
Lepidolite (K(Li,Al)3(Al,Si,Rb)4O10(F,OH)2)
mineral
Milky Quartz
Silicon Dioxide (SiO2)
mineral
Eudialyte
Na15Ca6Fe3Zr3Si(Si25O73)(O,OH,H2O)3(Cl,OH)2
mineral