This material is distinctly Arizona and comes from the North Eastern part of the state known as the Petrified Forest. While petrified wood comes from many locales, this species of 'wood' is known for it's variety and brilliant spectrum of colors. Scattered across a barren landscape are giant logs from an ancient forest, fossilized for millions of years.
Now, before you go accusing me of stealing from the park, you can relax. All the petrified wood I have came from legitimate sources and none has been pilfered from the national park. Because the geologic area extends beyond the park to private property, it is possible to acquire the material from private vendors, regardless of what the Holbrook tourist shop owners tell you.
My buddy Joe is a retired landscaper who lives in Cave Creek. He regularly purchases large quantities of petrified wood and brings it to Phoenix for re-sale to landscapers and other creative masons. He always lets me paw through any new loads for the best lapidary material.
As much as I like rainbow petrified wood, it can be exasperating to work with. It's often so fractured that cutting on the slab saw only fragments and threatens the blade. Then there are the pieces where I think I've got a perfect, fracture-less stone, that only reveals cracks during the final polish stage. In cutting a lot of the material I've learned what to look for in rough to avoid frustration. Much of the material I cut has been excavated from deep underground where temperatures are more constant and not subject to the fracturing of surface heating/cooling.
If you've been to the Petrified Forest, perhaps you have also heard of the conscience pile. This is a large pile of stones that have been returned via parcel from all parts of the world. Not only do visitors feel guilty for pilfering their souvenirs, but there is a reported curse on those who sneak a rock out of the park. Rest assured, all my petrified wood is only full of good mojo!