fossil

Petrified Wood

Silicified Wood (SiO2)

Hardness of 7 on the Mohs scale, varied earthy colors like brown, grey, and red, waxy to vitreous luster, and cryptocrystalline quartz structure.

Identified November 10, 2026More fossil →

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Physical properties

Hardness of 7 on the Mohs scale, varied earthy colors like brown, grey, and red, waxy to vitreous luster, and cryptocrystalline quartz structure.

Formed through permineralization, where organic wood material is replaced by minerals like silica over millions of years.

Used for decorative objects, lapidary arts, jewelry, and prized by fossil collectors.

The cellular structure of the original wood is often perfectly preserved, allowing microscopic identification of ancient tree species.

Identified by its wood-like grain and high hardness that scratches glass; commonly found in sedimentary rock layers worldwide.

Probable fossil-bearing rock or mineral concretion

Unidentified carbonate-rich concretion with a possible fossil inclusion

Likely fossil oyster shell

Fossilized bivalve shell; exact species cannot be identified from the image

Crinoid Stem Fossil in Matrix

Phylum Echinodermata, Class Crinoidea

Fossiliferous limestone (likely a crinoidal or shell-fragment limestone)

Bioclastic limestone, composed chiefly of calcite (CaCO₃)

Porous limestone pebble

Calcite-rich limestone (primarily CaCO₃); exact identification is uncertain from the image

Weathered fossil bone fragment (identification uncertain)

Fossilized bone; exact taxon and mineral composition cannot be determined from the image