fossil

Petrified Wood

Silicified Wood (SiO2 / Quartz pseudomorph after wood)

Hardness: 6.5 to 7 on the Mohs scale. Color: Brown, tan, cream, black, and white banding. Luster: Waxy to vitreous (polished). Structure: Hexagonal (microcrystalline quartz). Cleavage: None, conchoidal fracture.

Hardness: 6
Color: Brown, tan, cream, black, and white banding
Luster: Waxy to vitreous (polished)

Identified July 24, 2026More fossil →

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Physical properties

Formation & geological history

Formed when plant material is buried by sediment and protected from decay due to oxygen lack. Mineral-rich water flowing through the sediment deposits minerals in the plant's cells, replacing organic matter with silica over millions of years.

Uses & applications

Used in lapidary arts, jewelry, decorative polished displays, paperweights, and educational collections.

Geological facts

Petrified wood preserves detailed cellular structures of ancient trees, allowing paleobotanists to identify tree species from millions of years ago.

Field identification & locations

Look for distinct wood grain patterns, annual growth rings, and bark-like textures that have been replaced by dense chalcedony or jasper. Commonly found in sedimentary deposits, riverbeds, and gravel bars worldwide.

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