fossil

Iron-stained fossiliferous rock, possibly fossil wood

Likely silicified/petrified wood in iron-rich silica matrix; exact identification requires microscopy

AI-generated identification · may be incorrect

Brown to rusty-orange, glossy granular surface with fibrous or cellular-looking patterns and a gray-green matrix; likely quartz/chalcedony with iron oxides. Quartz hardness ~7, noncleavable, vitreous to waxy luster, specific gravity ~2.6.

Identified August 29, 2026More fossil →

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Physical properties

Formation & geological history

Silica-rich groundwater can replace organic tissue during burial, preserving wood texture; iron oxidation produces the reddish-brown staining. The age depends on the host formation and cannot be determined from the image.

Uses & applications

Used as a decorative lapidary material, cabochons, polished slabs, and fossil specimens; generally not suitable as a construction stone when collected as a small specimen.

Geological facts

Petrified wood may preserve growth rings, rays, vessels, and cellular detail even after complete mineral replacement; red coloration commonly comes from hematite or goethite.

Field identification & locations

Look for repeated cellular structure, growth-ring geometry, conchoidal fracture, and quartz-like hardness; common deposits occur in volcanic ash beds and sedimentary basins worldwide, including Arizona and Indonesia.