Chalcedony in Matrix (likely Agatized Coral or Chert)
Silicon Dioxide (SiO2)
Category
Browse organic material (likely a fruit or berry) specimens identified by the Rock Identifier community.
Chalcedony in Matrix (likely Agatized Coral or Chert)
Silicon Dioxide (SiO2)
Chert (often called Flint when dark or worked)
Cryptocrystalline silica (SiO2)
Shark Tooth Fossil
Elasmobranchii fossil (likely Carcharias or Odontaspis sp.)
Fossil-bearing sedimentary rock, possibly fossil wood or bone
Indeterminate silicified/carbonate fossil in sandstone or mudstone
Petrified Wood
Silicified Wood (primarily Quartz/Chalcedony, formula SiO2)
Limestone with Gastropod Fossil
Sedimentary Calcium Carbonate (CaCO3) with Gastropoda inclusion
Chert (often called Flint or River Stone)
Microcrystalline Quartz (SiO2)
Fossil Shark Tooth
Chondrichthyes (class); likely Lamniformes (order) fossilized in Apatite/Hydroxyapatite
Pearls (likely freshwater cultured pearls)
Pearl: nacre, primarily aragonite (CaCO₃) with conchiolin
Megalodon Shark Tooth (Partial Fossil)
Otodus megalodon (fossilized in Calcium Phosphate/Apatite)
Chert (often called Flint or Agate nodule)
Cryptocrystalline Quartz (SiO2)
Chert (often called Flint or River Pebble)
Chert (Microcrystalline Quartz, SiO2)
Quartzite with inclusions
Quartzite
Chert (v. Flint)
Sedimentary Cryptocrystalline Quartz (SiO2)
Chert (Jasper nodule)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Petrified Wood (Agatized/Silicified Wood)
Silicified Wood (SiO2)
Amber
Succinite (fossilized tree resin)
Limestone with Fossil inclusions
Fossiliferous Limestone (CaCO3)
Fossilized Shark Tooth
Chondrichthyes (Class) - likely Carcharodon or Otodus genus
Polished/tumbled calcite
Calcite (calcium carbonate, CaCO₃)
Chert (Jasper/Chalcedony variant)
Microcrystalline Quartz (SiO2)
Chert (Jasper/Limonitic Chert)
Microcrystalline Quartz (SiO2)
Chert (Yellow Jasper/Flint)
Microcrystalline Quartz (SiO2)
Conglomerate
Clastic Conglomerate (Lithic-rich)
Fossil gastropod shell
Fossilized marine gastropod; exact genus/species requires locality and examination
Sandstone (likely Fossilized Wood or Concrete Simulacrum)
Arenite / Silicified Wood / Anthropogenic Concrete
Petrified Wood
Silicified Paleoxylon (SiO2)
Jasper (Petrified Wood Variety)
Silicon Dioxide (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Fossilized Shark Tooth (Eroded)
Carcharodon sp. or Otodus sp. fragment (likely)
Chert / Flint
Chert (SiO2)
Petrified Wood
Silicified wood (Quartz, Chalcedony, or Opal)
Chert (Yellow Jasper/Flint)
Microcrystalline Quartz (SiO2)
Fossil Shark Tooth
Carcharadon sp. (likely Carcharodon carcharias or similar Lamniformes)
Chert (Brecciated Chert)
Silicon Dioxide (SiO2)
Petrified Wood
Silicified wood (primarily SiO2)
Chert (Flint with Iron Staining)
Silicon Dioxide (SiO2)
Puddingstone (Quartzite Conglomerate with Jasper inclusions)
Metaconglomerate (Silicon Dioxide, SiO2)
Chert (Jasper variety)
Cryptocrystalline Quartz (SiO2)
Chert (Gray Chalcedony)
Microcrystalline Quartz (SiO2)
Fossilized Megalodon Tooth Fragment
Otodus megalodon (Carcharocles megalodon fossil)
Petrified Wood
Silicified wood (Quartz/Chalcedony replacement)