Gaspare, I�m not sure the TK ring was cast as a ring, meaybe it was cast as a band, but it was cast. Take a look at other WWII skull rings - they were pressed, no doubt. But each piece is 90% identical. On TK rings is too much differences. And too much tool marks. See pictures below, I can�t see any tool marks, which were finishing the ring. And these rings were pressed in thousands and thousand pieces!
