fossil

Petrified wood

Silicified wood; commonly quartz (SiO₂) replacing original woody tissue

AI-generated identification · may be incorrect

Typically Mohs 6.5–7, brown to honey-orange with darker grain-like banding, and vitreous to waxy luster. It preserves wood texture; quartz has a trigonal crystal structure, no cleavage, and specific gravity near 2.65.

Identified September 21, 2026More fossil →

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Physical properties

Formation & geological history

Buried wood was gradually mineralized as silica-rich groundwater replaced cell walls, often during the Cenozoic or Mesozoic; the exact age cannot be determined from the image. It forms in volcanic-ash-rich sediments, floodplains, and sedimentary basins.

Uses & applications

Used for cabochons, carvings, bookends, polished slabs, and display specimens; larger pieces serve as decorative stone. It is generally a lapidary and collecting material rather than a structural stone.

Geological facts

The wood anatomy—growth rings, rays, or cellular texture—can remain visible despite complete mineral replacement. Colors may come from iron oxides, manganese, carbon, or other trace elements.

Field identification & locations

Identify it by unmistakable wood grain or cellular patterns, very high hardness, and a heavy, stone-like feel; it will not scratch easily with a steel knife. Common sources include Arizona, Madagascar, Indonesia, Australia, and Argentina.