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, IIRC. Fire assay is alive and well. Over 5000 years old and still going strong.
I am not an AZ etc, I am an Okie geologist. I have one of their catalogs. Good stuff, some you can't find easily.
Lou H.
> I think that "Syossetbutch" is simply tentatively identifying the very >old,
>> but well-established, analysis method for gold and silver known as "Fire
>> Assaying". It was the favoured goldfield method since it used a minimum
>> of equipment that couldnt be built on site. I once did such an assay
>> whilst a student. The details are recorded in "Standard Methods of
>> Chemical Analysis" by Wilfred W Scott ScD, published by D Van Nostrand Co
>> Inc, Volume 1. My copy is a fifth adition published in 1939. I will >fax
>> a copy to "Syossetbutch" if he privately sends me his number.
>>
>> It relies on extracting the gold and silver into a lead button which is >then
>> melted and oxidised on a bone ash crucible which absorbs the molten lead
>> oxide. The remaining button is all the gold and silver which is weighed
>> and then parted in acid to free the gold. I belive the assayer kept the
>> buttons as his fee.
>>
>> Bob
>>
>>
>> > that's certainly interesting- worked in the gold mines of Nevada for 20
>> > years as chemist and metallurgist and I've never seen that approach >> > .........
>> >
>> >
>> > > tho ore needs to be ball milled and then melted with fluxes. The end >> > result
>> > > will the be a homogeneous button or ingot and an assay will then be >> > performed.
>> > > You can figure out the content per pound after results.
>> > > Butch
>> >
>> >
>>
>>
>