African Plant Acts Like a Diamond Detector

Outside of jewelry stores, diamonds are pretty tough to find — so difficult, in fact, that despite spending $7 billion over the past decade and a half, mining companies have found so few new deposits that at this point, they’ve pretty much given up even trying.

But the search might get a little easier, thanks to a recent discovery that a certain African plant seems to grow only atop the type of geological formation in which diamonds are found.

It all started when Florida International University geologist and research professor Stephen E. Haggerty, who also happens to be chief exploration officer of Youssef Diamond Mining Co., went on a field trip to northeastern Liberia in 2013. Haggerty was in search of  a Kimberlite pipe, a carrot-like formation of rock that forms from magma and is pushed up from deep inside the Earth’s interior by volcanic eruptions. Though Kimberlite pipes don’t always contain diamonds, but they’re the primary source of the ones near the surface that are accessible to miners.

Haggerty found his Kimberlite pipe, but he also noticed something else. Rising out of the ground above the formation was a spiny, palm-like plant, Pandanus candelabrum, known to locals at a pamaya.

Further investigations on foot, by vehicle and from the air revealed that the odd-looking plant seemed to grow only in areas where diamond-bearing Kimberlite pipes are present, apparently because of the chemical composition of the soil above them.

“We don’t know if this plant can grow anywhere else where there aren’t kimberlite pipes present. It’s too early to tell,” Haggerty explained in a FIU press release. “The roots of the plant are typical of swampy areas, but for Liberia, it appears to be kimberlite-specific.”

The discovery, which Haggerty further detailed in an article for the journal Economic Geology, could make diamond prospecting a lot more efficient, by providing a conspicuous clue as to where diamonds might be found.

But the discovery has a few caveats. Only about 60 of the 6,000 pipes that have been discovered over the past century and a half have contained enough diamonds to make them worthwhile to mine, and only seven have turned out to contain so-called “super deposits” that make them highly lucrative, according to Bloomberg. And some of the last frontiers for diamond exploration are in the frozen Arctic regions of Russia and Canada, where the plants are not found.

From Discovery News