When Colombian emerald cutter Misael Angel Rodriguez was offered a large chunk of broken trapiche emerald in September 2012, he very nearly passed on the bid. The rough portion weighed nearly 370 ct and was covered in a black carbonaceous coating, with only a glimpse of green to suggest that it even contained emerald. Several other conocedores, or experts, had already declined to buy it, which added to Rodriguez’s concerns. Placing a bid on it was an expensive gamble: The piece was large and presumably mined at Muzo, Colombia’s historic emerald source. “But what secret does it hold?” Rodriguez wondered.
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