Photos provided by Andy Mason, UK, digitally processed and grouped by Jock Dempsey.
The two tools above are very similar yet different. At the top is a ball stake. These have a sphere or more than 50% of a sphere on a shank. The one below is a mushroom stake. These have anywhere less than 50% of a spherical surface. These are general rules, not hard and fast.

Note the swelling on the taper of the mushroom stake from striking it with a hammer. This is common abuse on simple stakes.

Again we have two stakes, a msuhroom and a ball. From the details they both appear to be forged. There is green paint under the red.