The long, strange story of the Bahia Emerald
In the northeastern Brazilian state of Bahia, not far from the city of Pindobaçu, the land is creased like an accordion. There, the earth’s crust has been squished into a series of granite ridges separated by scrub-filled valleys. These folds are rich with the elements beryllium and chromium, which have worked their way into the cracked rock and cooled to form green hexagonal crystals—emeralds. Starting in the 1960s, thousands of prospectors, known in Portuguese as garimpeiros, have flocked here to mine. Descending hundreds of feet down shafts no wider than manholes, they risk their lives to hunt for the gemstones.
One of these shafts sits below a farm owned by an elderly man. One day in early 2001, according to an investigation by Brazil’s National Department of Mineral Production, a garimpeiro there emerged from the ground with an emerald formation far larger than anyone had ever seen. It was a dark, tombstone-size hunk of shale, with a dozen greenish columns jutting out like sticks of Kryptonite. Weighing 840 pounds, the rock matrix contained an emerald estimated to be 180,000 carats in size. At the time of its discovery, it was the largest uncut emerald in the world.
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