Home Tour Physics Chemistry Earth Science Environment Scams Lesson Plans
Introduction Ore Processing Fire Assaying

Previous Fire Assaying Today (cont'd) Next
  1. As the lead is reduced, it drops through the liquid rock sample and collects (forms an amalgam with) the silver and gold that was contained in the rock.  The lead with gold and silver collects at the bottom.

  2. After the set of crucibles is heated and the rock is all reacted to make a glass that pours easily and separates completely from the lead button, the crucible is removed from the furnace and the glass is poured off to the waste below the hole in the table top.  The lead button, more dense and viscous at the bottom of the crucible, is poured into the cast iron mold.
  3. The liquid sample is poured into a mold so the glass slag and lead containing gold and silver (called the button) separate cleanly and solidify.  
Previous Fire Assaying Today (cont'd) Next


Home Tour Physics Chemistry Earth Science lEnvironment Scams Lesson Plans