Good Morning!
My experience has primarily been with producing a saleable dore product. In that world, lead is often used as a collector metal which is later cupelled to produce a gold/silver dore.
In limited instances, a miner may want a purer product to sell or keep. Most of the hardrock and placer operations I have seen have up to 35% silver in their gold. If a miner wanted to use chemical refining to produce high purity gold, would it make sense to smelt the concentrates using sterling as a collector metal and skip the cupelling step? You may still need to adjust the silver/copper content to inquart the gold. You may overshoot and require more time and nitric to remove the silver and copper but you would avoid cupelling and dealing with lead oxide fumes.
Thoughts? Has anyone tried this?
SRM
My experience has primarily been with producing a saleable dore product. In that world, lead is often used as a collector metal which is later cupelled to produce a gold/silver dore.
In limited instances, a miner may want a purer product to sell or keep. Most of the hardrock and placer operations I have seen have up to 35% silver in their gold. If a miner wanted to use chemical refining to produce high purity gold, would it make sense to smelt the concentrates using sterling as a collector metal and skip the cupelling step? You may still need to adjust the silver/copper content to inquart the gold. You may overshoot and require more time and nitric to remove the silver and copper but you would avoid cupelling and dealing with lead oxide fumes.
Thoughts? Has anyone tried this?
SRM