Cupel beads of non-noble metal?

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Joined
Mar 31, 2012
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Can anyone shed some light on what metals might show up in a cupel after fire assaying other than gold, silver and the PGMs?
 
As far as I understand cupelling will all metals, which form oxides with atmospherical oxygen when heated, do so (together with lead), dissolve into the melted litharge and get sucked into the boneash cupel.

So, all other metals will be left in their metallic state. If I should make a guess, I'd say it would be all metals less reactive than copper.

(only from reading, not tried cupelling and fireassaying in practice yet)
 
Just a guess but one metal I can think of that "might" not respond to cupeling would be tungsten due to its "high" resistance to oxidization & extremely high melting point

There are other metals that take "special" conditions to process as well that "may" (guessing again) to process (separate/refine)

Kurt
 
If the metal is not oxidized or oxidized properly by the torch in the cupel, (or the metal is reduced in the flame or melt),it would also melt to elemental metal with the values of the button.
 
kurtak said:
Just a guess but one metal I can think of that "might" not respond to cupeling would be tungsten due to its "high" resistance to oxidization & extremely high melting point

There are other metals that take "special" conditions to process as well that "may" (guessing again) to process (separate/refine)

Kurt
Definitely tungsten as I have had high tungsten samples leave residue in the finished cupel. Was wondering about tantalum and a couple others.
 
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