fossil

Petrified Wood

Fossilized Wood (silicified wood)

Hardness: 6.5 to 7 on the Mohs scale. Color: White, cream, tan, beige, brown, and light yellowish tones. Luster: Vitreous to waxy. Structure: Cryptocrystalline quartz preserving original wood grain, cellular layers, and ring structures. Cleavage: None (conchoidal fracture). Specific Gravity: ~2.6-2.65.

Hardness: 6
Color: White, cream, tan, beige, brown, and light yellowish tones
Luster: Vitreous to waxy

Identified July 26, 2026More fossil →

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Physical properties

Formation & geological history

Formed through permineralization, where organic wood material is buried under sediment or volcanic ash and gradually replaced over millions of years by silica-rich groundwater solutions, typically during the Cenozoic or Mesozoic eras.

Uses & applications

Popular as decorative display specimens, lapidary art, bookends, polished slabs, landscaping elements, and educational fossil collections.

Geological facts

This specimen clearly displays preserved fibrous plant structures along one side and solid microcrystalline chalcedony/agate replacing the core, demonstrating the transition from fibrous wood texture to solid petrified stone.

Field identification & locations

Identified in the field by parallel wood-like grain and bark-like layered structures that react like hard silica (scratches glass) rather than soft organic wood. Common in sedimentary basins, ancient volcanic deposits, and gravel beds worldwide, including Washington state, Oregon, and Arizona.