Re: Pimples along silver cuts :clueless[1]:
As Silver or any other metal solidifys it shrinks as this is happening the gates which allow new molten metal to enter the mold freezes so as to cut off new metal filling in where the shrinkage is happening. This results in small voids ( shrinkage porosity). Casters do try to minimize this to the extent they can and some are better at this than others. In a rolled product this shrinkage porosity is further reduced by rolling anealing then rolling more. This added to the inhrent nature of an ingot to shrink as a whole which reduces shrinkage porosity to begin with makes for a better lloy for engraving.
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