Petrified Wood
Silicified Wood (SiO2)
Category
Browse organic (geological relative) specimens identified by the Rock Identifier community.
Petrified Wood
Silicified Wood (SiO2)
Chert / River Jasper
Microcrystalline Quartz (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Chert (with Quartz Veining)
Chert (formula: SiO2)
Petrified Wood
Silicified Wood (SiO2)
Shale
Shale (fine-grained clastic sedimentary rock)
Limestone (Concretionary or Tufa)
Calcium Carbonate (CaCO3)
Grey and White Chert (Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Jasper (Red-Brown)
Silicon Dioxide (SiO2) with Iron Oxide impurities
Chert (Quartz Variety)
Microcrystalline Silica (SiO2)
Chert (specifically Tan/Yellow Chert)
Chert (Microcrystalline or Cryptocrystalline Silica, SiO2)
Petrified Wood
Silicified Wood (SiO2)
Chalk
Calcium Carbonate (CaCO3)
Ambergris
Ambergris (Coprolite-adjacent organic substance)
Moss Agate
Cryptocrystalline Quartz (SiO2 with Manganese or Iron Oxide inclusions)
Petrified Wood (Silicified Wood)
Silicified Wood (primarily Chalcedony/Quartz, SiO2)
Petrified Wood
Silicified Wood (SiO2)
Dyed Howlite (simulating Lavender/Purple Jade or Charoite)
Howlite: Ca2B5SiO9(OH)5 (when natural)
Silty Shale or Mudstone
Siltstone/Mudstone (Clastic Sedimentary Rock)
Black Tourmaline (Schorl)
NaFe3Al6(BO3)3Si6O18(OH)4
Black Chert
Chert (microcrystalline quartz)
Chert (Cherty Shale / Flint)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Fossilized Coral (Petoskey Stone or Tabulate Coral)
Scleractinia or Tabulata (CaCO3 - Calcium Carbonate)
White Marble
Recrystallized Calcite (CaCO3)
Chert Nodule
Microcrystalline Quartz (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Petrified Wood (Agatized/Silicified Wood)
Silicified Wood (SiO2)
Orange Calcite
Calcite (Calcium Carbonate, CaCO3)
Moqui Marble (Shaman Stone)
Iron Oxide Concretion (composed primarily of Quartz sand with Hematite/Goethite shell)
Possible fossilized ammonite or concretion
Indeterminate fossil specimen; possibly an ammonoid mold/cast in iron-rich sedimentary rock
Jasper
Jasper (Silicon Dioxide, SiO2)
Green Jasper (with Quartz veining)
Jasper (Silica-rich microcrystalline variety of Quartz), formula: SiO2
Banded Chert
Microcrystalline Quartz (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Chert (White/Light Tan)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert (Nodular)
Chert (SiO2 - Microcrystalline Quartz)
Chert Pebble with Quartz Veins
Microcrystalline Quartz (SiO2)
Chert (specifically Tan/Brown Chert)
Chert (SiO2)
Chert (Jasper variation)
Silicon Dioxide (SiO2) - Microcrystalline Quartz
Travertine (Tufa)
Chemical Limestone (CaCO3)
Petrified Wood
Silicified Wood (primarily Quartz / Chalcedony: SiO2)