Looking for some help on the Assayer. It is a 4R Potosi. Obviously, pre-Pillars/Waves. The Assayer mark has the curve associated with a B, but the lower bubble seems to not be as curved. If it is a "B", then it is a Ballesteros (Juan or Hernando). But my questioning eyes raise the possibility that it could be an R where the lower leg isn't flaired but squared off. Any ideas?