Petrified Wood
Silicified Wood (SiO2)
Category
Browse organic (paper and cellulose) specimens identified by the Rock Identifier community.
Petrified Wood
Silicified Wood (SiO2)
Jasper
Agate/Jasper (Microcrystalline Quartz, SiO2)
Petrified Wood
Silicified wood (SiO2)
Mookaite Jasper
Silicified Radiolarite (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Chert (Limestone-hosted Pebble)
Sedimentary Cryptocrystalline Quartz (SiO2)
Banded Chert / Flint
Microcrystalline Quartz (SiO2)
Sandstone (likely Fossilized Wood or Concrete Simulacrum)
Arenite / Silicified Wood / Anthropogenic Concrete
Ambergris
Ambergris (Coprolite-adjacent/Organic secretion)
Graphite-veined Quartzite
Meta-sedimentary Quartzite with Carbonaceous/Graphitic Inclusions (SiO2 + C)
Green Jasper (with Quartz veining)
Jasper (Silica-rich microcrystalline variety of Quartz), formula: SiO2
Petrified Wood (Agatized/Silicified Wood)
Silicified Wood (SiO2)
Chert (Yellow Jasper variant)
Microcrystalline Quartz (SiO2)
Petrified Wood
Silicified wood (primarily quartz, SiO2)
Petrified Wood (Silicified Wood)
Silicified Wood (primarily Chalcedony/Quartz, SiO2)
Banded Chert (Flint/Jasper variety)
Microcrystalline Quartz (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Petrified Wood
Silicified Wood (SiO2 - Quartz/Chalcendony replacing organic matter)
Fossilized Gastropod (Snail)
Class Gastropoda (internal mold or 'steinkern')
Chert (Brecciated or Veined)
Silicon Dioxide (SiO2)
Chert (Flint Pebbles)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Chert Pebble with Quartz Veins
Microcrystalline Quartz (SiO2)
Limestone Pebble
Calcite-rich Sedimentary Rock (CaCO3)
Petrified Wood
Silicified wood (SiO2)
Chert (Flint)
Silicon Dioxide (SiO2)
Ironstone Concretion / Limonite Node
Ferruginous Sedimentary Rock (composed primarily of Limonite FeO(OH)·nH2O and Goethite)
Banded Chert (Ironstone/Jasper)
Cryptocrystalline Quartz (SiO2) with Iron Oxides
Flint
Chert (Cryptocrystalline Quartz, SiO2)
Petrified Wood
Silicified wood (Quartz/Chalcedony - SiO2)
Petrified Wood
Silicified Wood (SiO2 - Silicon Dioxide)
Glauconitic Sandstone (or Greensand)
Glauconitic Siliciclastic Rock (Containing (K,Na)(Fe,Al,Mg)2(Si,Al)4O10(OH)2)
Banded Chert
Cryptocrystalline Quartz (SiO2)
Jasper (Red-Brown)
Silicon Dioxide (SiO2) with Iron Oxide impurities
Graphite
Graphite (C)
Chert (often called Flint or Jasper locally)
Chert (Microcrystalline Quartz, Formula: SiO2)
Chert (variations include Flint or Jasper)
Silicon Dioxide (SiO2)
Chert (Grey-Green Var.)
Silicon Dioxide (SiO2)
Chert (Quartz Variety)
Microcrystalline Silica (SiO2)
Chert (Nodule)
Silicon Dioxide (SiO2)
Chert (White/Light Tan)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Coal
Bituminous coal (Complex organic sedimentary rock)
Ambergris
Ambergris (Coprolite-adjacent organic substance)