This is made from very unusual Spec Burl lumber. When this tree was growing, something told it to produce thousands of buds which never became limbs. I have seen this pattern before in a small area of a board, but never covering the entire board. I purchased the whole log from a local sawmill. The owner said in his 50+ years in the lumber business he had never seen it like that  before.
 
The 2" diameter hole has an aluminum rim.
 
I built one other sphere with this lumber, and there is enough for maybe two smaller ones and then it is gone for good.