Chert (Yellow/Brown variety)
Chert (SiO2)
sedimentary
Category
Mineral (Silicate Replaced Organic Material)
Browse mineral (silicate replaced organic material) specimens identified by the Rock Identifier community.
Chert (variations include Flint or Jasper)
Silicon Dioxide (SiO2)
sedimentary
Petrified Wood
Silicified Wood (SiO2)
sedimentary
Petrified Wood
Silicified wood (primarily Silicon Dioxide - SiO2)
metamorphic
Chert (Nodule)
Silicon Dioxide (SiO2)
sedimentary
Chert (Nodule)
Microcrystalline or Cryptocrystalline Silica (SiO2)
sedimentary
Lapis Lazuli
Lapis Lazuli (Rock composed primarily of Lazurite (Na,Ca)8(AlSiO4)6(S,Cl,SO4,OH)2, Calcite, and Pyrite)
metamorphic
Fossiliferous Rock (likely Dinosaur Fossil in Matrix)
Permineralized Vertebrate Fossil (Calcium Carbonate/Silica replaced bone material)
sedimentary
Fossil Shark Tooth (Sand Tiger or Mackerel Shark)
Carcharias sp. or Otodus sp. replaced by Hydroxylapatite/Calcium Carbonate
sedimentary
Amber
Succinite (fossilized resin, C10H16O)
mineral
Fossilized Sand Tiger Shark Tooth
Carcharias taurus / Striatolamia macrota (mineralized as Hydroxylapatite/Francolite)
sedimentary (fossil)
Chert / Flint
Chert (varietal name for microcrystalline quartz). Chemical formula: SiO₂
Mineral
Petrified Wood
Silicified wood (primarily SiO2)
sedimentary
Chert (Light Grey / Flint variant)
Cryptocrystalline Quartz (SiO2)
sedimentary
Petrified Wood
Silicified Wood (SiO2)
mineral
Red Jasper
Jasper (Silicon Dioxide, SiO2)
sedimentary
Limonite (Ironstone)
Limonite (mixture of hydrated iron oxides, primarily Goethite α-FeO(OH))
mineral
Chert (Jasper/Flint variety)
Silicon Dioxide (SiO2)
sedimentary
Prehnite
Calcium aluminum silicate hydroxide - Ca2Al(AlSi3O10)(OH)2
mineral
Fossilized Coral
Anthozoa (Fossilized)
Sedimentary / Fossil
Petrified Wood
Silicified Wood (SiO2)
sedimentary
Jasper (specifically Yellow Jasper and Red Jasper)
Silicon Dioxide (SiO2) with iron oxide inclusions
sedimentary
Tiger's Eye (often misinterpreted as Gold Ore in this context)
Pseudomorph of Quartz after Crocidolite (SiO2)
metamorphic
Druzy Chalcedony/Quartz on Fluorite core
Silicon Dioxide (SiO2) on Calcium Fluoride (CaF2)
mineral
Petrified Wood
Silicified wood (primarily SiO2 - Silicon Dioxide)
mineral
Green Sandstone
Glauconitic Sandstone
sedimentary
Chert (often called Flint or Jasper locally)
Chert (Microcrystalline Quartz, Formula: SiO2)
sedimentary
Yellow Beryl (Heliodor)
Beryllium aluminum silicate (Be3Al2Si6O18)
mineral
Petrified Wood
Silicified wood (primarily SiO2)
metamorphic
Unakite
Epidotized Granite (Fe, Ca, Al silicate + KAlSi3O8)
metamorphic
Yellow Jasper (Iron-stained Chert)
Silicon Dioxide (SiO2) with iron oxide (Limonite/Goethite) inclusions
sedimentary
Petrified Wood
Silicified Wood (SiO2)
mineral
Pyrite
Iron Sulfide (FeS2)
mineral
Green Jasper (with Quartz veining)
Jasper (Silica-rich microcrystalline variety of Quartz), formula: SiO2
sedimentary
Turritella Agate (Fossiliferous Chert)
Silicified Elimia tenera (Fossiliferous Chalcedony)
sedimentary
Jasper
Jasper (Silicon Dioxide, SiO2)
sedimentary
Petrified Wood (Silicified Wood)
Silicified fossil wood (SiO2)
metamorphic
Kaolinite (Chalky Clay)
Kaolinite (Al2Si2O5(OH)4)
sedimentary
Green Common Opal
Hydrated Silica (SiO2·nH2O)
mineral
Glass
Amorphous Silicon Dioxide (SiO2)
mineraloid
Fossilized Shark Tooth
Carcharodon carcharias (fossilized) / Hydroxyapatite permineralized with silica or iron
sedimentary
Chert (with Limestone matrix)
Silicon dioxide (SiO2)
sedimentary