• Home
  • news
  • What are fire assay crucibles and how do they work?
What are fire assay crucibles and how do they work?

Products A monolithic rammed liner, a slip plan, and possibly an outer or quick-change crucible–basket assembly are required to back the crucible. Bottom pouring may require atomising or metering devices. The casting manufacturing system allows for custom shapes such as ladles or tundishes.

Fire Assay Ceramics

FIRE ASSAY CRUCIIBLES are used for the preparation of the lead button and precious metal sample for cupellation. These crucibles have a high level of mechanical strength, erosion resistance, and the ability to withstand severe heat shocks from an assay furnace. TSR is enhanced by the inclusion of fused silicona in the mixture.

SCORIFIERS do the same job, but remove the gangue without the use of a furnace.

Cupellation is when the lead is oxidized into litharge (PbO). Most of this is absorbed by CUPEL. At the end, a bead is left of gold, silver and any other precious metals. Cupels are made of magnesite and have a controlled pore structure that allows for quick absorption of litharge, leaving an easily-removed pore.

BULLION BLOCKS are available in a range of 4 to 14 cups per block and the same magnesite material that the cupels.