This bowl was handmade out of chestnut and has some spalting and natural inclusions.
These holes are formed by cavities in the bark of the tree that are carefully preserved when making the bowl.
This bowl was cored out of a big chunk of black locust.
With this type of coring multiple pieces can be made out of one block of wood.
In this case I was able to make 3 bowls out of the same piece.