fossil

Petrified wood

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

AI-generated identification · may be incorrect

Brown and tan, with visible wood-grain texture and a rough, earthy-to-glassy surface. Typically Mohs 6.5–7, microcrystalline quartz, no cleavage; specific gravity about 2.0–2.6. The image alone cannot confirm hardness or composition.

Identified October 6, 2026More fossil →

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Physical properties

Formation & geological history

Buried wood was mineralized as silica-rich groundwater replaced or filled its tissues, preserving the grain. Petrification occurs in sedimentary settings over geological time; this specimen’s age and locality cannot be determined from the photo.

Uses & applications

Collected as a fossil and used for display, carvings, and lapidary work; larger deposits have been used decoratively.

Geological facts

Petrified wood retains the form and growth patterns of wood while its original organic material is largely replaced by minerals.

Field identification & locations

Look for continuous wood grain, knots, or growth rings with stone-like hardness and weight; common deposits occur in volcanic-ash-rich sedimentary beds worldwide. Similar-looking wood or mineral casts may require testing to confirm.