Petrified wood
Silicified fossil wood, primarily quartz (SiO₂) replacing cellulose
fossil
Category
Mineral (Organic)
Browse mineral (organic) specimens identified by the Rock Identifier community.
Learn about Mineral (Organic) in the encyclopedia
View all →
Concretionary Sandstone
Clastic Sedimentary Rock (Sandstone with secondary mineral cementation)
sedimentary
Starfish Fossil
Asteroidea fossil
fossil
Fossil Shark Tooth
Chondrichthyes tooth fossil
fossil
Turtle Stone / Septarian Nodule (Water-worn)
Septarian Concretion
sedimentary
Pyrite on Limestone
Iron Disulfide (FeS2) in Calcium Carbonate (CaCO3) matrix
sedimentary (matrix) / mineral (inclusion)
Amber (Raw Copal)
Fossilized Plant Resin (Gummite/Succinite)
mineral
Moss Agate
Silicon Dioxide with inclusions (SiO2 + Mn/Fe oxides)
mineral
Moss Agate
Silicon Dioxide (SiO2) with Manganese/Iron Oxide inclusions
mineral
Amber
Succinite (fossilized tree resin)
mineral
Pink Opal
Hydrated Silica (SiO2·nH2O)
mineral
Moss Agate with Quartz Druzy
Chalcedony with inclusions (SiO2)
mineral
Moss Agate
Silicon Dioxide with inclusions (SiO2 + Fe/Mg/Mn/Chlorite)
mineral
River Cobble (Sandstone)
Arenite (primarily SiO2)
sedimentary
Jasper
Silicon Dioxide (SiO2)
mineral
Petrified Wood
Silicified Wood (SiO2)
mineral
Amber
Succinite (a specific common type) or Fossilized Tree Resin (C10H16O)
Mineraloid
Jasper or Agate (Chalcedony)
Silicon Dioxide (SiO2) with impurities
sedimentary
Chert (Green Chert)
Microcrystalline silica (SiO2)
sedimentary
Aragonite (Star Cluster or Twinned variety)
Aragonite (Calcium Carbonate, CaCO3)
mineral
Amber (Dark/Black Variety)
Succinite (Resinite), C10H16O
mineral
Petrified Wood
Silicified wood (Quartz/Chalcedony/Opal replacing organic matter)
sedimentary
Petrified wood
Silicified wood, commonly quartz (SiO₂) replacing woody tissue
fossil
Petrified wood
Silicified fossil wood, commonly quartz/chalcedony (SiO₂) replacing woody tissue
fossil
Likely graphite-rich metamorphic rock (graphitic schist)
Graphitic schist; chiefly carbon (graphite) with quartz, mica, and possibly sulfides
metamorphic
Chert / Flint
Silicon Dioxide (SiO2)
sedimentary
Petrified Wood
Silicon Dioxide (SiO2) - Calcified / Silicified Wood
sedimentary
Black Chert
Carbonaceous Chert (Silicon dioxide, SiO2)
sedimentary
Petrified Wood
Silicified Wood (SiO2)
sedimentary
Chert (Jasper/Flint variety)
Silicon Dioxide (SiO2)
sedimentary
Anthracite Coal
Carbon (with organic impurities)
sedimentary
Pearl (in Marcasite Jewelry)
Biogenic Calcium Carbonate (primarily Aragonite, CaCO3)
gemstone
Petrified Wood
Siliconized Wood (SiO2)
sedimentary
Petrified Wood
Silicified Wood (SiO2 - Silicon Dioxide)
sedimentary
Petrified Wood
Silicified wood (primarily Silicon Dioxide, SiO2)
metamorphic
Moss Agate
Silicon Dioxide with inclusions (SiO2 + impurities)
mineral
Black Jasper
Black Jasper (Silicate mineral - SiO2)
sedimentary
Moss Agate
Silicon dioxide (SiO2) with mineral inclusions
Mineral
Chert (Yellow Jasper)
Microcrystalline Quartz (SiO2)
sedimentary
Fossilized Shell Fragment
Invertebrate marine fossil, likely calcium carbonate replacement
fossil
Banded Marble (Egg Carving)
Metamorphosed Limestone (predominantly CaCO3)
metamorphic
Polished fossilized wood (likely petrified wood)
Silicified wood; primarily quartz (SiO₂) replacing wood tissue
fossil