Tehuitzingo, Puebla — An international group of scientists with the Institute of Geology of UNAM, discovered an outcrop of microdiamonds in rocks called cromitas in Tehuitzingo, Puebla.
The geological value of this finding is unique since it allows researchers to study the terrestrial surface of ancient materials of the mantle of the Earth, the inner layer that is between the nucleus and the outer crust of the planet.
Although the microdiamonds cannot be extracted due to their tiny size, barely three microns, the microdiamonds show that they can form at a lower temperature and pressure than known up until now, explained Colás Ginés, a member of the Caribbean Research Group.
This discovery generates unprecedented scientific information about the materials of the terrestrial mantle, while the finding could be useful for the synthetic diamond industry to generate stones at less extreme temperature and pressure, which would greatly reduce its cost, the expert explained.
“Mexico is one of the countries with more outcrops of mantle rocks, with more than 20. They represent ancient sutures of the ocean. Imagine that the Pacific closes and because of this, the rocks of the mantle remain on the earth’s crust and we have them emerging,” he said.
Other diamonds found in the world have been formed under conditions of high pressure and temperature, but those found in Puebla have a compositional variation.
“The chromite metal is formed at 1,200 degrees Celsius and the diamonds around 1,000, but they also need very high pressure, in the order of gigapascals, and they are only achieved in the mantle,” he stressed.
The group responsible for the find is formed by more than one twenty scientists from various universities in Mexico, Spain, Australia, Peru, Sweden, Germany and Cuba. The results of his research were published in the scientific journal Geology.