Darwin missed this one completely. In fact, it even amazes, and delights, the potter in me, as to how designs move about in the studio and pieces evolve into other pieces. These evolutions are often brought about by a customer comment or request. 
For example, I was looking for a design to work on while I was demonstrating at different events. I needed a piece that would take a while to carve. Due to the fact these pieces are carved in the “green” state, transporting them can be precarious. So the fewer pieces one takes, and the more carving one can do on one plate makes life less stressful. Thus, this piece with the diamond border was born. It takes a good deal of time to do and is a good design to show many people how sgraffito is actually performed.
(women should now skip down 5 lines)
MEN: this plate says in German ” everyone says I have such a pretty wife “. Every husband should have this plate in reserve because at some point in your life, you will need to do something especially nice to make up for something you have done. This will not solve problems, but will put you on the right road to recovery.
A customer I met at the 18th century market at Historic Locust Grove asked if I could put that diamond pattern on a butter dish, and as you’ll hear me say a lot as a potter is, “sure”. Then the thought process begins.
Once I figured out how to position the plate in relation to the cover, all went relatively well and it turned out to be quite a pretty little piece.
So who knows what the butter dish is now evolving into: a tankard, a chamberstick, a pitcher, a …