The foam came to our business 10-something years ago from a German company called m-pore. They were making it in their facilities. I machined some experimental parts out of it, and with the scraps I got the permission from my boss to do whatever I want.
I used aluminum foil to make a quick mold around a piece of foam. Then casted slow curing clear epoxy to fill the piece. I actually did not plan much at that point, just wanted to see would it come out any good for something.
I sawed off the foil mold, and then decided to combine the piece with cocobolo. Originally I thought of making a knob for my car shift stick, but then I went for a knife handle.