Green Tree Agate
This came from the playhouse collection, and from what I can gather, it originates in India. No idea how it got to Arizona.
This agate is a unique white matrix with green dendrites throughout. Of the stuff I've cut so far, much of it is fragmented by dirty brown crystal strands that make it appear stained. Only a small portion of the slab typically has enough white/green to cab. With all the little pits and hidden fractures it is challenging to cut, but the result can be quite unique.
If you do a Google search on the stuff, it apparently has a lot of metaphysical benefits... if you believe in that sort of thing.