I wonder if anyone can help identify this beautiful heavy bowl? It is very clearly marked on its base: CH-8338-3 WK but I haven't had any luck trying to decipher them so far

It measures 12 cm high x 16.5 cm in diameter and weighs roughly 1.4 kg and has these raised polished circles with a polished rim and base. In between it looks a bit like its been sandblasted, but is smoother than that sounds. The base has an indent in its centre but it doesn't feel like it's a pontil mark - so maybe mould blown?
I originally bought it to sell on but can't bear to part with it yet......