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

Previous Fire Assaying Today (cont'd) Next
  1. One of the series of powdered rock samples is weighed in preparation for adding to the fire brick crucibles.The whole flux is thoroughly mixed with a known amount of carefully sampled powdered rock in a fire brick crucible.  This crucible withstands the heat of the furnace and is thick enough that only some of the inner wall reacts with the fluxes to become a part of the glass slag, which floats on top of the molten lead.
  2. The weighed powdered rock sample is added to the crucible.  The assayer keeps a list that relates the sample identification to the position of the crucible.The crucible is heated so the  mixture of flux and rock sample melts (at a temperature lower than that of the rock alone as controlled by the flux composition).  
Previous Fire Assaying Today (cont'd) Next


Home Tour Physics Chemistry Earth Science lEnvironment Scams Lesson Plans