Write some historical fiction eg the diary of a European salt merchant whose prosperity could come from supplying Christopher Columbus. His diary could explain how salt was used and where it came from.
In the case of Spanish and Portuguese explorers it’s likely to have come from West African kingdoms. Studying this trade provides a valuable context for more common studies of Africa, which are often confined to the slave trade. For resources visit www.khyber.demon.co.ukhistoryafricawafrica.htm
