fossil

Polished petrified wood

Silicified wood; commonly quartz/chalcedony (SiO₂) replacing cellular tissue

AI-generated identification · may be incorrect

Typically Mohs hardness 6.5–7, vitreous to waxy luster, brown, red, cream, and gray colors, with preserved wood grain and cellular patterns. It has no prominent cleavage, a microcrystalline quartz structure, and specific gravity around 2.5–2.7.

Identified August 24, 2026More fossil →

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Physical properties

Formation & geological history

Buried wood was mineralized as silica-rich groundwater replaced organic tissue, often during volcanic or sedimentary burial. Many commercial pieces formed during the Mesozoic–Cenozoic, though age varies by deposit.

Uses & applications

Used for decorative carvings, polished slabs, bookends, tabletops, and collectible specimens; lapidary-quality material is valued for pattern and color.

Geological facts

The wood’s anatomy can remain visible because silica preserves growth rings, vessels, and cellular structure. Red tones commonly reflect iron oxides, while yellow or brown areas may contain additional iron-bearing minerals.

Field identification & locations

Identify it by recognizable grain or cellular texture, very high hardness, heavy weight, and quartz-like polish; common sources include Arizona, Indonesia, Madagascar, Brazil, and Australia. This large polished freeform appears to be a decorative petrified-wood piece.