Geologists from the University of Heidelberg came to an interesting conclusion by studying old and rare samples of the mineral zircon, which contain inclusions of graphite. It turned out that they can retain traces of life.
The light carbon found in zircon crystals, as a remnant of earlier life, opens up new possibilities for studying the early period of the Earth. Geologists explain this by the fact that the mineral grains of zircon are formed from magma.
But millions of years ago, the heated remains of organisms turned into carbon dioxide and methane gases. And then they were deposited in the form of graphite in the mineral zircon at about 700 °C.
The research took place under very difficult conditions. Indeed, in zircon crystals, it was necessary to identify intact graphite inclusions, the size of which in some cases was only a few micrometers.
It is worth recalling that zircon is one of the oldest minerals on the planet, which can "tell about more than 96% of the history of the Earth."
Source: sciencedirect.com