They would make a killing, and the West Africans would just keep on buying madly. Local African Emerald prices here in Zambia would soon make Sotheby's and that other First World place look mild. But give all their due I say. And what would happen is that so many people would make fortunes overnight, that there would be a real drive towards acquiring more product to sell. Very soon the available Emeralds would be depleted though.
Emeralds are like that, really.
And then suddenly there would be a new deposit discovered somewhere, selling cheap in a rural area. Of course cheap by this time is horrendously expensive, with Colombian prices child's play. People would pour money and fortunes and stolen IMF funds and unilateral aid and bilateral aid and what else into this new Emerald material. The West Africans would cry for more and more, having set up offices by now with long queues in front. Of course the new find's Emeralds are not so new after all.