For over a century, mineral prospectors have known that a rock known as kimberlite often contains diamonds. Find kimberlite, and you’ve got a much better chance at finding diamonds.
Now, a geologist has an even easier way to find diamonds—just look for a palm-like plant called Pandanus candelabrum . The stilted, shrubby tree appears to prefer growing on kimberlite-derived soils, which are high in potassium, phosphorous, and magnesium. The soil appears at the top of pipes, or tubes, of the igneous rock which has been pushed to the surface from an underlying source of magma, carrying rocks and minerals—including diamonds—to the surface.
Though kimberlite pipes are found around the world, P. candelabrum is only found in West Africa, including in Liberia, where Stephen Haggerty, a professor of geophysics at Florida International University, made the connection between the two. He published his findings in Economic Geology.
The P. candelabrum /kimberlite link could change the way diamonds are mined in the region. Here’s Eric Hand, reporting for Science:
If the plant is as choosy as it seems to be, diamond hunters in West Africa will have a simple, powerful way of finding diamond-rich deposits. Prospectors are going to “jump on it like crazy,” says Steven Shirey, a geologist specializing in diamond research at the Carnegie Institution for Science in Washington, D.C.
It’s possible that similar associations may be discovered elsewhere on the planet. Botanists and geologists have long known that certain plants have evolved to grow on specialized soils. California, for example, is home to a unique type of grassland only found on serpentine soils, in part because the plants have evolved to cope with the soil’s low fertility and high levels of nickel and chromium, two toxic metals.
Hand also points out that not only could the palm-like plant serve as a living signpost for prospectors, it could also minimize some of the environmental impact of diamond mining in West Africa. Rather than relying on costly strip mining, companies could instead focus their efforts on kimberlite pipes, which are now much easier to find.
Photo credit: Jakob Fahr/iNaturalist (CC BY-NC)