For the first time, traces of early life have been discovered inside a 2.5 billion-year-old sapphire

Posted:

October 22, 2021 20:11 GMT

The sapphire sample studied most likely contains fractions of pure carbon (graphite) of biological origin. They are the remains of some ancient microorganisms from the time before multicellular life appeared on Earth.

An international team of researchers led by Professor Chris Yakimchuk from the University of Waterloo (Canada) has discovered traces of carbon that correspond to a primitive being inside one of the world’s oldest gemstones, a sapphire that dates back about 2.5 billion years. years, according to a release from the University.

The gem was found in Greenland, where some of the world’s oldest deposits of this gem are located, when Yakimchuk and his team sought to better understand the processes of formation of a mineral, corundum, by studying Greenland sapphires. Article published in rough geology reviews.

“The graphite inside this sapphire is really unique. This is the first time we’ve seen traces of ancient life in rocks containing sapphire,” Yakimchuk said.

The researchers analyzed the isotopic composition of carbon atoms in graphite. It turns out that 98% of all carbon atoms have an atomic mass of 12, and a few of them are heavier.

Based on the fact that living matter consists mainly of lighter carbon atoms, because it requires less energy to be incorporated into cells, the scientists concluded that carbon atoms represent life in the form of microorganisms, possibly cyanobacteria.

Graphite was found in rocks more than 2.5 billion years ago, which corresponds to a time on planet Earth when oxygen was not abundant in the atmosphere and life existed only in the form of microorganisms and membranes of algae.

Moreover, scientists believe that graphite not only associated sapphire with ancient life forms, but was essential to its formation. This mineral changed the chemical composition of the surrounding rocks to create favorable conditions for the formation of sapphire, which in other cases would have made its formation impossible.