On 19 Jun, 12:15, mike wrote:
I have a good quality and quite old shovel which has serious layers of
all sorts of muck - including old cement - very securely stuck to it.

Any suggestions for cleaning - other than a cold chisel and hammer?

Try just using the hammer. A lot of cement type rubbish will fall off
if you beat the shovel around a bit. Hitting the shovel on the ground
should remove some. The steel can flex more than the cement so it
falls off. There will still be some left though. Then a wire brush in
a drill or angle grinder may work or even a chemical such as cement
remover.

John