fossil

Petrified Wood

Silicified wood (Quartz/Chalcedony replacement)

Hardness of 6.5 to 7 on the Mohs scale, colors range from brown, grey, and tan to vibrant reds and yellows, vitreous to dull luster, amorphous crystal structure (microcrystalline quartz)

Identified August 3, 2026More fossil →

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Physical properties

Hardness of 6.5 to 7 on the Mohs scale, colors range from brown, grey, and tan to vibrant reds and yellows, vitreous to dull luster, amorphous crystal structure (microcrystalline quartz)

Formation & geological history

Formed when organic plant material is buried in an oxygen-free environment such as volcanic ash or sedimentary mud, where groundwater rich in dissolved silica slowly replaces the cellular structure of the wood with minerals over millions of years

Uses & applications

Used for ornamental objects, polished display specimens, lapidary art, jewelry, and in educational or geological collections

Geological facts

The petrification process can preserve microscopic details of the original plant structure, allowing scientists to study ancient ecosystems dating back hundreds of millions of years

Field identification & locations

Identified by retaining the distinct grain patterns, rings, or bark texture of wood while possessing the extreme hardness, weight, and cold touch of stone; commonly found in areas with ancient river basins or volcanic ash deposits

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