Photos provided by Andy Mason, UK, digitally processed and grouped by Jock Dempsey.
This cone stake is not seen in any of my books or catalogs. The faint parting line and texture indicate that this is a cast tool.

The unusual thing about this cone shape is its limited capacity. If the axis of the cone was the same as the shank or even somewhere between the angle it is and vertical it could be used to work the center of a much larger cone. It seems this stake was designed for a very specific job or class of work.

Like many old tools the age and origins are often hard to determine. Again, this could be of Continental origin as easily as English.

Dimensions
11″ tall (~280 mm)
Cone, 4″ diameter, 3″ tall (~100 x 76 mm)