11.8" Petrified Wood (Woodworthia) Round - Arizona
This is a beautiful round of petrified Woodworthia from the Chinle Formation of Arizona. Woodworthia is one of the more uncommon types of petrified wood within the petrified forests of Arizona. The polishing work on this piece is fabulous. There is a cut mark along one edge of this petrified wood slab and it doesn't maintain a uniform thickness all the way across (.5" to .9").
Petrified wood is the name given to wood that has been turned into stone (fossilized) through the process of permineralization. All of the organic matter becomes replaced by minerals, while much of the original structure such as tree rings in retained. For this to happen the wood needs to be buried in an environment both low in oxygen (preventing decomposition) and with flowing, mineral-laden water. The coloration is due to the various minerals that are present during fossilization. For example red colors are due to iron compounds, greens due to copper, etc.