Petrified Wood
Silicified Wood (SiO2 permineralization)
Category
Browse organic gemstone (not a mineral) specimens identified by the Rock Identifier community.
Petrified Wood
Silicified Wood (SiO2 permineralization)
Coprolite
Coprolite (fossilized feces)
Petrified Wood
Silicified wood (primarily SiO2)
Dinosaur Fossil (Skull)
Dinosauria fossilis (Petrified Hydroxyapatite / Calcium Carbonate)
Petrified Wood
Silicified Wood (primarily SiO2)
Geode with Quartz Crystal Cavity
Silicon Dioxide (SiO2) in Calcareous/Siliceous Matrix
Petrified Wood
Silicified wood (primarily Quartz/Chalcedony, SiO2)
Geode (Unopened)
Silica-rich concretion (SiO2)
Fossilized Shark Tooth (Fragment)
Elasmobranchii fossil (likely Cretalamna or Squalicorax genus)
Amber
Succinite (C10H16O)
Moss Agate
Cryptocrystalline Quartz (SiO2 with manganese or iron oxide inclusions)
Carbonaceous Chondrite (CV3 type)
Carbonaceous Chondrite (CV3 group)
Petrified Wood
Silicified Wood (SiO2)
Chert / Flint
Cryptocrystalline Quartz (SiO2)
Flint (Chert Node)
Silicon Dioxide (SiO2)
Chert
Microcrystalline Quartz (SiO2)
Tiger's Eye
Silicon Dioxide (SiO2) with fibrous inclusions
Petrified Wood
Silicon Dioxide (SiO2)
Chert
Microcrystalline Quartz (SiO2)
Epidote
Epidote - Ca2(Al2,Fe3+)3(SiO4)3(OH)
Sandstone Concretion
Arenaceous concretion (primarily SiO2 with Fe2O3 staining)
Tiger's Eye
Pseudomorph of Quartz after Crocidolite (SiO2 with inclusions)
Amber
Succinate (Fossilized Tree Resin)
Amber with Inclusion
Succiniferous fossil resin (C10H16O)
Chert (specifically Blue Chert or Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Chert (Green Chert/Jasper)
Chert (primarily Microcrystalline Quartz, SiO2)
Petrified Wood
Silicified Wood (primarily SiO2)
Chert (specifically Yellow/Honey Jasper variety)
Cryptocrystalline Quartz (SiO2)
Ammonite Fossil (Small Pyritized or Calcitized Internal Mold)
Ammonoidea
Favosites Fossil (Honeycomb Coral)
Favosites (Extinct genus of Tabulate Coral)
Jasper (Petrified Wood variant)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Ironstone Concretion (Limonite/Hematite Nodules)
Ironstone (principally Limonite FeO(OH)·nH2O or Hematite Fe2O3 mixed with silica/clay)
Fluorite
Calcium Fluoride (CaF2)
Jasper with Quartz Vein
Silicon Dioxide (SiO2) with impurities
Sandstone Concretion
Clastic sedimentary rock (primarily Quartz SiO2)
Chert (vuggy variety)
Microcrystalline silica (SiO2)
Sandstone (with carbonaceous plant fragments)
Arenite (composed primarily of SiO2)
Petrified Wood
Silicified Wood (SiO2)
Dendritic Moss Agate
Chalcedony (Silicon Dioxide, SiO2) with inclusions
Chert / Chalcedony
Microcrystalline Quartz (SiO2)
Epidote
Calcium aluminum iron silicate (Ca2(Al, Fe)3(SiO4)3(OH))