fossil

Petrified Wood

Silicified Wood (Per mineral content: SiO2, Quartz/Chalcedony)

Hardness: 6.5-7 on Mohs scale. Color: Brown, reddish-brown, grey, dark grey to black. Luster: Vitreous to earthy/waxy. Structure: Preserves original plant cell architecture and tree ring patterns. Specific Gravity: ~2.6-2.8.

Hardness: 6
Color: Brown, reddish-brown, grey, dark grey to black
Luster: Vitreous to earthy/waxy

Identified July 25, 2026More fossil →

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Physical properties

Formation & geological history

Formed via permineralization, where organic wood material is buried under sediment or volcanic ash, and dissolved minerals (mainly silica) replace the plant tissues cell-by-cell over millions of years.

Uses & applications

Used in lapidary arts, decorative items, bookends, jewelry, landscape ornamentation, and educational fossil collections.

Geological facts

Entire ancient forests can become petrified, such as the Petrified Forest National Park in Arizona, USA. The colors in petrified wood come from trace elements like iron, manganese, and copper.

Field identification & locations

Identified by original wood grain texture, annual growth rings, bark-like exterior, and a cool, heavy mineral feel compared to modern wood. Commonly found in sedimentary basins and volcanic ash beds worldwide.

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