Understanding carbon dating
Photo by Robert Weldon/GIA, courtesyof Jose Guillermo Ortiz, Colombian Emerald Co.
Colombia is the traditional source of the world’s finest emeralds, including the famed trapiche crystals, with their distinctive texture resembling a wheel with six spokes.
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This gemological curiosity, found exclusively in the black shales of the country’s western emerald zone, is linked to the peculiar structural geology of the deposits.
The study presents a review and update on Colombian trapiche emeralds, followed by a three-dimensional examination of the crystals combined with spectroscopic and chemical analyses.
It is also influenced by natural exchange with the land and ocean.The authors show that trapiche emerald growth starts at the beginning of the decompression that is responsible for local supersaturation of the fluid.The hydrothermal fluid comes in contact with the black shale matrix, favoring the formation of emerald seed crystals.As the visualization shows, carbon dioxide in the atmosphere can be mixed and transported by winds in the blink of an eye.For several decades, scientists have measured carbon dioxide at remote surface locations and occasionally from aircraft.
The OCO-2 mission represents an important advance in the ability to observe atmospheric carbon dioxide.