
Medieval Africans Had a Unique Process for Purifying Gold with Glass - Thevet
https://www.atlasobscura.com/articles/medieval-african-gold
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DoctorOetker
What does the material efficiency for the gold look like? Is there room for
improvement? Can statistical physics tell us something about purification
effficiency? Is there room for improvement?

Or is it strictly of historical interest?

Can this decrease mercury pollution of the environment, especially by the
poorer small scale gold refinement? Or has that already been succesfully
replaced world wide?

Edit: I have no clue why this got downvoted? I don't mind being downvoted, but
please don't squander an opportunity for interesting discussion?

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gwern
Yes, I'm a little curious too. Presumably Africans had lead available (right?)
so does the choice of glass imply that it was superior to lead? Or, since
Europeans also had glass, is it vice-versa (maybe lead requires better
furnaces to be workable or some other technical requirement)?

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DoctorOetker
Glass has a much higher melting temperature than lead, so it's the other way
around, but this might explain why Europeans stayed with lead.

I don't know if the Africans lacked lead, perhaps lead was simply valued more
than scrap glass?

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max_
"...According to Walton, Europeans in the 10th and 11th centuries purified
their gold through cupellation, a process in which lead is mixed with gold
laced with impurities, and then heated in a furnace until the droplets of
purer gold can be skimmed off. But in the case of medieval West Africans,
“They were taking the ore and other raw materials from the river and mixing it
with glass,” says Walton. Since gold is inert, it doesn’t fully dissolve into
melted glass, while impurities and other materials do, making this “a really
novel way of using recycled glass material.”....."

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agumonkey
so basically molten glass sponge .. very interesting

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mynegation
Africa is such a huge continent, why not say “Medieval Malians”? How much of
an information does “Medieval Eurasians invented gunpowder” have?

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djtriptych
Because many of the currently known national boundaries didn't exist back
then, and the tribal delineations would be wholly unfamiliar to their
audience.

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bobberkarl
Just to say you're not completely right. the mali empire existed back then.

