Uncovering Diamonds with Bacterial Clues
The mystique surrounding the creation of diamonds deep within the Earth's crust is nothing short of captivating. These enchanting gemstones are born under immense pressure and heat in the Earth's upper mantle, transforming simple carbon molecules into shimmering treasures. As geologists scour the Earth's surface in search of these hidden gems, a surprising ally has emerged - soil microbes.
Tiny Geochemists with a Big Impact
German biologists and geologists discovered that microorganisms are profoundly responsive to the subtlest geochemical alterations in their environment. These microscopic wonders interact with minerals at the nanoscopic and micron levels, leaving telltale signs in their microbial realms.
Researchers, led by Rachel Simister at the University of British Columbia in Vancouver, ventured to explore whether deep-lying rocks might influence the microbial makeup of the soil. In a lab setting, they introduced Arctic tundra soil microbes to both their natural habitats and samples spiked with tiny amounts of kimberlite.
Diamonds in Disguise: Microbial Indicators
The findings were nothing short of astounding. The tiniest traces of kimberlite altered the bacterial species composition dramatically. Sequencing the ribosomal DNA of the bacteria revealed that the number of specific bacterial species surged dramatically in the presence of kimberlite, while others dwindled significantly.
Among the 65 indicator species, these bacterial characters represented an astounding 60 percent of the whole microbial community after the incubation period. Prior to the experiment, they accounted for a mere 0.6%.
Field Symphony: Microbes as Accurate Sensors
To test the validity of these findings, the researchers performed a field experiment in the Northern Territories of Canada, where a hidden kimberlite deposit, Kelvin-Kimberlit, lay hidden 150 meters beneath rock and four meters of glacial sediment.
The results were nothing short of impressive. Wherever the kimberlite lay beyond 154 meters, the bacteria identified in the laboratory were present in larger numbers. Indeed, these microbial indicators proved to be more accurate than conventional geochemical analyses, which sometimes produced false positive results in kimberlite-devoid sample sites.
Diamonds in the Rough: A New Exploration Tool
This discovery ushers in a new era of identifying diamond-rich kimberlite deposits. Particularly in regions where receding glaciers and thawing permafrost yield new and previously undiscovered resources, this methodology could be a game-changer.
This innovative technique, however, extends beyond just diamonds. DNA sequencing of soil microbes could prove invaluable in the hunt for other mineral resources, such as copper. Unique bacteria populations could serve as indicators for various types of ore deposits, simplifying the discovery and development process of valuable raw materials.
As Bianca Phillips, a co-author from the University of British Columbia, eloquently puts it, "Microbes represent a new tool for the geological exploration of mineral deposits. This could not only save time and money but also streamline the discovery and development of valuable raw material deposits." The world of microbes promises to yield many yet-unexpected applications for research and industry.
[1] Geological Survey of Canada. (2021). Kimberlites. Retrieved March 10, 2023, from
