Thanks. That is what I remember from reading years ago. Research the word, left, and see what you can find. The history and usage of a word has always interested me. Thanks for your help.
Glad to help.
In southern Mali, an American mining engineer told me that in their gold mining activities, they were finding hand dug tunnels 60 feet underground which had been dug 300 years ago by slaves. The gold was taken to northern Mali to Timbuktu (which had a reputation in Europe as a source of gold). There it was traded for salt!
In this particular Malian village we could buy coffee tabletop sized slabs of salt in the market which had been brought down by donkey or camel from the Timbuktu area.