The spade was one of my wife's which had by happy chance sheared across the joint to the blade. I put it on Dad's anvil and battered it to a chisel point with a 2-pound lumpy, then tidied the edge up with a grinder.

It's bloody tough steel! The results aren't all that pretty, but they're going under the ground so I'm not all that fussed. The thing's also very slightly curved and I can't face trying to do anything about that. It really was a job of work getting it this far.