fossil

Fossilized wood (petrified wood)

Silicified fossil wood; commonly quartz (SiO₂) replacing wood tissues

AI-generated identification · may be incorrect

Typically Mohs 6.5–7, brown to tan with dark organic-looking bands, earthy to glassy luster, and preserved wood grain; quartz is non-cleavable with conchoidal fracture and specific gravity around 2.6.

Identified September 12, 2026More fossil →

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Physical properties

Formation & geological history

Buried wood was mineralized when silica-rich groundwater replaced cellular tissues, often during the Mesozoic or Cenozoic; the exact age and locality cannot be determined from the image.

Uses & applications

Used as a lapidary material for polished slabs, cabochons, ornaments, and collectible specimens; large pieces may be used decoratively.

Geological facts

This specimen appears to preserve vascular grain and growth or cellular textures, characteristic of petrified wood rather than ordinary brown stone.

Field identification & locations

Identify by visible wood grain, hardness, heft, and lack of splintering; common sources include Arizona, Utah, Oregon, Indonesia, Madagascar, and Argentina. A locality label or microscope examination would improve identification.