Chert (Flint)
Microcrystalline Quartz (SiO2)
sedimentary
Category
Mineral (Silicate Replaced Organic Material)
Browse mineral (silicate replaced organic material) specimens identified by the Rock Identifier community.
Learn about Mineral (Silicate Replaced Organic Material) in the encyclopedia
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Petrified Wood
Silicified Wood (primarily SiO2)
sedimentary
Chert / Chalcedony
Silicon Dioxide (SiO2)
sedimentary
Yellow calcite fragment
Calcite (CaCO₃), likely honey/yellow calcite
mineral
Jasper
Microcrystalline Quartz (SiO2)
sedimentary
Jasper
Silicon Dioxide (SiO2) microcrystalline quartz
sedimentary
Dinosaur Bone (Gembone)
Silicified Dinosaur Bone (SiO2 replacing organic tissue)
sedimentary
Pyrite
Iron Sulfide (FeS2)
mineral
Unidentified Dark Mineral or Rock
Indeterminate (Likely Silicon Dioxide or Carbon-based)
mineral
Leopard skin jasper (orbicular jasper)
Microcrystalline quartz (SiO₂), commonly with iron-oxide and other silicate inclusions
metamorphic
Petrified Wood
Silicified wood (Quartz/Chalcedony - SiO2)
sedimentary
Jasper
Microcrystalline Quartz (SiO2)
sedimentary
Petrified Wood / Fossilized Wood
Silicified Wood (Silicon Dioxide - SiO2)
fossil
Chert (Nodule)
Cryptocrystalline Quartz (SiO2)
sedimentary
Jasper
Silicon Dioxide (SiO2) microcrystalline quartz
sedimentary
Jasper
Silicon Dioxide (SiO2) with impurities
sedimentary
Petrified wood
Silicified wood, chiefly microcrystalline quartz (SiO₂)
fossil
Petrified Wood
Silicified Wood (SiO2)
sedimentary
Tumbled petrified wood
Silicified wood; primarily microcrystalline quartz (SiO₂)
fossil
Dinosaur Bone (Petrified/Agatized)
Permineralized Dinosauria Bone (Silicate Replacement)
fossil
Possible fossilized bone or tooth fragment
Indeterminate fossilized vertebrate material; mineralized hydroxyapatite replaced or coated by silica/carbonate
fossil
Fossilized Shark Tooth
Chondrichthyes (Class) fossil
fossil
Fossilized bone fragment, possibly dinosaur or large mammal bone
Fossil bone; mineralized apatite (carbonate-fluorapatite), commonly Ca₅(PO₄)₃(F,OH)
fossil
Polished brecciated jasper
Jasper, opaque microcrystalline quartz (SiO₂), likely brecciated jasper with iron-oxide and dark silicate inclusions
mineral
Fossilized Shark Tooth
Eocene Lamniformes (Mackerel Shark clade)
fossil
Mosasaur Tooth Fossil
Mosasaurus sp.
fossil
Petrified Wood
Silicified Wood (SiO2)
fossil
Shark Tooth Fossil
Elasmobranchii fossil (likely Carcharias or Odontaspis sp.)
fossil
Orbicular jasper
Siliceous microcrystalline quartz (chalcedony), commonly sold as ocean jasper
rock
Polished fossil bone fragment
Fossilized bone, likely mammalian or reptilian; exact taxon cannot be determined from the image
fossil
Brecciated Chert
Sedimentary Chert (SiO2) with Calc-Silicate mineralization
sedimentary
Petrified Wood
Silicified wood (principally SiO2)
sedimentary
Pyrite
Iron Sulfide (FeS2)
mineral
Fossilized ammonite fragment
Ammonoidea; likely an ammonite suture-section specimen, commonly Jurassic–Cretaceous
fossil
Sand Tiger Shark Tooth
Carcharias taurus (fossilized)
fossil
Petrified Wood
Silicified Wood (SiO2)
fossil
Shark Tooth Fossil
Carcharodon / Otodus fossilized tooth (Calcium Phosphate / Hydroxyapatite)
fossil
Chert (Jasper-rich)
Silicon Dioxide (SiO2)
sedimentary
Chert / Chalcedony
Silicon Dioxide (SiO2)
sedimentary
Jasper
Microcrystalline Quartz (SiO2)
sedimentary
Red Jasper
Quartz (Silicon Dioxide) with Hematite inclusions, SiO2
mineral
Petrified Wood
Silicified Wood (SiO2)
sedimentary