fossil
Petrified Wood and Mixed Rocks
Silicified Wood (SiO2)
Mohs hardness 6.5-7, dull to vitreous or waxy luster, displays preserved fibrous or cellular wood structures, colors range from beige and tan to brown, dark grey, and reddish tones.
Identified More fossil →
Explore Petrified Wood and Mixed Rocks in the encyclopedia →Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Mohs hardness 6.5-7, dull to vitreous or waxy luster, displays preserved fibrous or cellular wood structures, colors range from beige and tan to brown, dark grey, and reddish tones.
Formation & geological history
Formed when plant material is buried by sediment and mineral-rich water flows through, replacing the organic matter with silica, calcite, or other minerals over millions of years.
Uses & applications
Popular among rockhounds and lapidary hobbyists for polishing, display specimens, jewelry making, and educational fossil collections.
Geological facts
Petrified wood can retain cellular details of the original tree bark and ring structures down to the microscopic level, often preserved by microcrystalline quartz (chert/agate).
Field identification & locations
Identified by fibrous, woody grain textures paired with the hardness and weight of stone. Commonly found in sedimentary basins, riverbeds, and ancient volcanic ash beds globally.
More like this
Other fossil specimens
Crinoid Stem Fossil in Matrix
Phylum Echinodermata, Class Crinoidea
fossil
Sedimentary Outcrop (Sandstone/Shale)
Sedimentary bedrock formation (variable composition)
sedimentary
Chert with Fossil Brachiopod
Microcrystalline Quartz (SiO2) with Calcitic Brachiopod inclusion
sedimentary
Fossilized Crinoid Stem in Limestone
Crinoidea (Class) in Calcium Carbonate (CaCO3) matrix
fossil
Fossiliferous Limestone
Limestone with embedded fossil cross-section
sedimentary
Fossiliferous Limestone
Fossiliferous Calcilutite / Biomicrite
sedimentary