Gemstones are usually created after carbon has been crushed and heated far below the Earth’s surface for billions of years – making them so desirable.
Now scientists in Australia say they have accelerated the process in just a few minutes – and at room temperature.
An international team of researchers led by the Australian National University (ANU) and RMIT University in Melbourne, Australia, said Wednesday that they had created two types of diamonds at room temperature using high pressure equivalent to 640 African elephants balancing on top of a ballet shoe.
Researchers say they have created two types of structurally different diamonds – one similar to those commonly worn in jewelry, and another type called Lonsdaleite, which is found naturally at the site of a meteorite̵
Synthetic diamonds themselves are not new and have already been created in laboratories since the 1940s in an attempt to find cheaper, ethical and environmentally friendly stones.
But researchers are excited to create such diamonds at room temperature, especially the harder Lonsdaleite diamond, which has the potential to be used to drill “super-solid” materials on minefields, they said.
“Creating more than this rare but extremely useful diamond is the long-term goal of this work,” said Xingshuo Huang, an ANU scientist working on the project. “The ability to make two types of diamonds at room temperature was exciting to achieve for the first time in our laboratory.”
Enormous torsional, sliding force
To form the diamonds, the researchers put enormous pressure to create a “torsional or sliding force” that they said caused the carbon atoms to move into place, said Jody Bradby, a physics professor at ANU.
“Natural diamonds typically form over billions of years, about 150 kilometers (about 93 miles) deep in the Earth, where there are high pressures and temperatures above 1,000 degrees Celsius (1,832 degrees Fahrenheit),” she said. “The twist in history is how we apply pressure.”
Dougal McCulloch, a physics professor at RMIT who led the study, and his team then used advanced electron microscopy techniques to take slices from the experimental samples to better understand how they were formed.
When the team examined the samples, they found veins of both ordinary and Lonsdale diamonds passing through them.
“Seeing these little rivers from Lonsdaleit and the ordinary diamond for the first time was just amazing and really helps us understand how they could form,” McCulloch said.
Researchers from the National Laboratory at the University of Sydney and Oak Ridge in Tennessee, USA also participated in the study.