Petrified Wood Object, United States

Tree rings and fibrous grain stay on show across a chunky block.

This petrified wood object is from Oregon, the United States. Petrified wood forms when buried timber is slowly replaced by silica-rich minerals, preserving the grain and ring structure of the tree in stone. Dark brown and gray growth lines fan outward across the top face, while the sides turn pale straw with vertical streaks of grain. Edges are rough and irregular, with small dark spots near the upper rim. It is 4.75 inches wide, 3 deep and 3 high.

Slow growth, and every ring kept as a receipt.