Petrified Wood Knot Log

An exceptional specimen. This knot log, from a petrified Araucarioxylon arizonicum, was entombed in volcanic ash 280 million years ago, long before being found in 2006 in Northern Arizona, just outside Petrified Forest National Park.

Petrified wood is the name given to a special type of fossilized remains of terrestrial vegetation. Over the course of thousands of years, inorganic materials in the groundwater surrounding this buried conifer seeped in and replaced the organic minerals via a process known as permineralization. During this petrification process, the plant's lignin and cellulose decay, while inorganic materials—in this case primarily quartz and iron oxides—essentially use the tree's organic structure as a scaffolding to build an exact rock copy of the specimen.

This species of extinct conifer, Araucarioxylon arizonicum, is the state fossil of Arizona, with this particular specimen's rarity and appeal coming from a number of factors. Its size is enormous, and the quality and flow of its color are stunning. It is no wonder that specimens found in this region are considered the world's finest and most sought after, with the knot log offered here being an exceptional example.