Very sturdy granite table which can swivel up to higher heights or swivel down to lower. 
55cm (21.5 inches) circumference.  About 2 inches deep.

I think this is a very unique piece. 

Some edges on the bottom of granite are rough - my guess is that it likely fell over at some point in  its life and chipped. But personally I have always thought it adds to the character. I bought it that way and it has never bothered me.