A team of Canadian scientists from the University of Waterloo have discovered signs of ancient life inside a 2.5 billion year old ruby. Corundum was found in Greenland.

The oldest rubies on the planet – gemstones composed of a mineral with a red tint – are found in Greenland. While searching for corundum in the North Atlantic Craton in southern Greenland, a team of researchers discovered an amazing find in one of them: graphite, a pure form of carbon. Scientists are confident that these may be the remains of ancient microbial life.

“The graphite inside this ruby ​​is truly unique,” said Chris Yakimchuk, professor at the Department of Earth and Environmental Sciences at the University of Waterloo in Ontario, Canada. “This is the first time we’re seeing signs of ancient life in ruby-bearing rocks.”

After conducting research, scientists found that graphite originated from an ancient form of life. At a time when ancient bacteria probably lived, there was not a lot of oxygen on the planet – an essential element for complex life. This is why the only organisms that could survive were tiny microbes and algae. It is believed that cyanobacteria were among the first living things on Earth. Over billions of years of converting sunlight into chemical energy, they gradually produced the oxygen needed for complex life to eventually evolve.

Graphite-containing corundum, while ancient, is hardly the oldest evidence of life on Earth. However, this is the first time that its remains have been found inside rubies. The results are published in the November issue of Ore Geology Reviews.