Evidence based speculation, page-52

I suppose what makes sense in terms of the costs to produce a valid assay scheme are not necessarily the same as what makes sense in terms of mining and processing an ore body, but it is interesting that you have fed your own holder bias by pointing out the use of NaCl to precipitate out the silver. Note however that gold is extracted by cupellation with lead. How does that process scale up to a mine processing circuit (not an assay circuit). Cuppelation involves another run through a furnace and the use of lead in some quantity. Once again what is the cost of lead per oz of gold extraction and is the lead reusable. Lead is also quite a nasty substance to be melting and using. Esh