Rock Identifier
Fossilized Wood (Petrified Wood) (Agatized wood (primarily SiO2)) — fossil
fossil

Fossilized Wood (Petrified Wood)

Agatized wood (primarily SiO2)

AI-generated identification · may be incorrect

Hardness: 6.5–7 on Mohs scale. Color: Tan, brown, and grey with some white quartz patches. Luster: Dull to waxy. Structure: Preserved botanical cellular structure (permineralization). Specific gravity: 2.6–2.9.

Hardness
6
Color
Tan, brown, and grey with some white quartz patches
Luster
Dull to waxy
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Physical properties

Hardness: 6.5–7 on Mohs scale. Color: Tan, brown, and grey with some white quartz patches. Luster: Dull to waxy. Structure: Preserved botanical cellular structure (permineralization). Specific gravity: 2.6–2.9.

Formation & geological history

Formed through permineralization, a process where organic material is replaced by minerals (usually silica) over millions of years. This specimen likely dates from the Paleozoic to Cenozoic eras and formed in an environment where wood was buried quickly by volcanic ash or sediment.

Uses & applications

Used for house decor, landscape gardening, lapidary arts (polishing into bookends or jewelry), and as scientific specimens for studying paleoenvironments.

Geological facts

Petrified wood can retain such fine detail that even microscopic cell structures and growth rings are visible. It is the state rock of several US states including Washington and Mississippi.

Field identification & locations

Identify in the field by looking for wood-grain patterns, bark textures, or knot structures in stones that are much heavier and harder than normal wood. Often found in riverbeds or dry badland areas.

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