The lead buttons are allowed to "open", that is to become molten. When the cupellation is "driving" or the lead is being absorbed into the cupel or driven off as lead oxide, the furnace is opened slightly to provide a draft. The lead is absorbed leaving behind a tiny dor¨¦ bead containing the gold and silver.
The cupels are allowed to cool. The dor¨¦ is then removed, brushed to remove any adhering cupel material and flattened using an anvil and bead hammer. At this point the dor¨¦ is weighed.
The dor¨¦ is then finished gravimetrically or by wet chemical digestion and analysis using Atomic Absorption Spectroscopy.

Crucible Cup For Melting	Pure Bone Ash Cupels	Mabor Cupel	Cupel Trays
Composite Bone Ash Tapered Cupels	Bone Ash Tapered Cupels	magnesium oxide and bone ash cupels	magnesium oxide and bone ash cupels
Magnesium sand cupel	Ceramic Couple	Plate cupel	Fire assay cupel

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