Green Sandstone (Glauconitic Sandstone)
Glauconitic Sandstone (K(Fe,Al)2(Si,Al)4O10(OH)2)
sedimentary
Category
Mineral (Silicate Replaced Organic Material)
Browse mineral (silicate replaced organic material) specimens identified by the Rock Identifier community.
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Chert (Nodule)
Microcrystalline Quartz (SiO2)
sedimentary
Chert (Jasper/Flint variety)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Chert Nodule
Microcrystalline Quartz (SiO2)
sedimentary
Coral Fossil (Hexagonaria)
Hexagonaria sp. (Silica-replaced)
fossil
Likely pyrite-bearing rock fragment
Pyrite, FeS₂, possibly in a dark host rock
mineral
Petrified Wood
Silicified Wood (SiO2)
metamorphic
Red Jasper
Microcrystalline Quartz (Chalcedony), SiO2
sedimentary
Petrified Wood
Silicified Wood (SiO2)
sedimentary
Chert (Cherty Shale / Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Polished jasper, likely orbicular or brecciated jasper
Jasper: microcrystalline quartz (chalcedony), SiO₂, colored by iron oxides and other inclusions
mineral
Jasper
Jasper (Silicon Dioxide) - SiO2
sedimentary
Chert (Flint)
Silicon Dioxide (SiO2)
sedimentary
Fossilized Wood / Petrified Wood
Petrified Wood (Silicified Flora)
fossil
Polished orbicular jasper (likely ocean jasper)
Jasper, microcrystalline quartz (SiO₂), with iron-oxide and other silicate inclusions
mineral
Fossilized wood or bone fragment
Indeterminate permineralized organic fossil; possibly silicified wood or fossil bone
fossil
Chert (Flint Nodule)
Microcrystalline and Cryptocrystalline Quartz (SiO2)
sedimentary
Elephant Skin Jasper
Microcrystalline Quartz (SiO2)
sedimentary
Chert (containing Fossil Inclusions)
Microcrystalline Quartz (SiO2)
sedimentary
Sandstone Concretion
Sedimentary Clastic Rock (Silicate-rich)
sedimentary
Chert (Jasper/Flint variety)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Petrified Wood
Silicified Wood (SiO2)
metamorphic
Fossilized Shark Tooth (fragment)
Elasmobranchii (Class) fossil
fossil
Petrified Wood
Silicified Wood (primarily SiO2)
metamorphic
Fossilized Wood (Petrified Wood) and Associated Rocks
Silicified Wood / Xylopal
fossil
Petrified Wood
Silicified Wood (SiO2 permineralization)
sedimentary
Petrified Wood (Agatized/Silicified Wood)
Silicified Wood (SiO2)
metamorphic
Likely amber-colored chert or chalcedony fragment
Microcrystalline quartz (SiO₂), possibly iron-stained chert; exact identification is uncertain from the image
mineral
Iron-rich chert or jasper
Microcrystalline quartz (SiO₂), commonly colored by hematite/goethite
sedimentary
Petrified Wood
Silicified Wood (SiO2)
mineral
Tumbled jasper
Jasper, an opaque microcrystalline variety of quartz (SiO₂), commonly containing iron oxides and other silicates
mineral
Chert (Nodule / Geode fragment)
Microcrystalline Quartz (SiO2)
sedimentary
Chert (Nodule)
Microcrystalline quartz (SiO2)
sedimentary
Jasper
Silicon Dioxide (Microcrystalline Quartz / Chalcedony)
sedimentary
Polished orbicular jasper
Siliceous microcrystalline quartz (chalcedony), SiO₂, with iron-oxide and other mineral inclusions
sedimentary
Petrified Wood
Silicified Wood (SiO2 permineralization)
fossil
Petrified Wood
Silicified Wood (primarily SiO2)
sedimentary
Moss Agate
Chalcedony (SiO2) with inclusions of hornblende or chlorite
mineral
Fossilized Bivalve Shell (Fossilized Clam)
Bivalvia (class) / CaCO3 (Calcium Carbonate)
fossil
Chert (Jasper/Flint)
Silicon Dioxide (SiO2)
sedimentary
Petrified Wood
Silicified Wood (SiO2)
sedimentary
Chert (Jasper nodule)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
sedimentary