The Zambian mine is the emerald mine everyone is talking about. From Walter Isaacson's biography: > [Errol and a Zambian busienessman] agreed on a price [for E

The Zambian mine is the emerald mine everyone is talking about. From Walter Isaacson's biography: > [Errol and a Zambian busienessman] agreed on a price [for Errol's plane], and instead of taking a payment in cash, Errol was given a portion of the emeralds produced at three small mines that the entrepreneur owned in Zambia. [...] > Errol, who never had an ownership stake in the mine, expanded his trade by importing raw emeralds and having them cut in Johannesburg. "Many people came to me with stolen parcels," he says. "On trips overseas I would sell emeralds to jewelers. It was a cloak-and-dagger thing, because none of it was legal." After producing profits of roughly $210,000, his emerald business collapsed in the 1980s when the Russians created an artificial emerald in the lab. He lost all of his emerald earnings. $210,000 in 1986 would be about $600,000 today.