It is cartainly a very early Michael Harris Fish, the most desirable kind - and it's gorgeous, but I don't think it is cobalt, just "normal" turquoisey blue.
Run and grab it - now - do not pass go, (but you might need to collect the £200) these very special (and button-rimmed to boot) Fish vases are scarce. Max your overdraft if you must, beg, borrow or steal the rest.......
(having said that, I don't know the price on it. I paid £350 for mine - it's the same colour - not cobalt, but mine's more triangular.)
I know exactly what you mean about your hand doing something before you realise it's done it - that's how I found my tiny little "Precious Baby Fish".
See you later, when it's yours!