Lab-made diamonds show drilling potential
Thursday, November 19th, 2020
A team of scientists led by the Australian National University and RMIT University have created two types of diamonds in the lab at room temperature.
Nanocrystalline diamond and Lonsdaleite were produced by the scientists, proving they can form diamonds at room temperature by applying high pressure within minutes.
Natural diamonds, in comparison, take billions of years to form in temperatures over 1000 degrees Celsius.
While the nanocrystalline diamond can have decorative uses, co-lead researcher Dougal McCulloch said Lonsdaleite had the potential to be used for cutting ultra-solid materials in mining applications.
Lonsdaleite has a different crystal structure to regular diamond and is predicted to be 58 per cent harder.
The team had previously created Lonsdaleite in the lab only at high temperatures. But this new discovery shows both Lonsdaleite and regular diamond can also form at normal room temperatures by just applying high pressures of 100 gigapascal (GPa) – equivalent to 640 African elephants on the tip of a ballet shoe.
Australian National University professor and lead researcher for the project Jodie Bradby said the carbon used to create diamonds was given a unique application of pressure.
“The twist in the story is how we apply the pressure. As well as very high pressures, we allow the carbon to also experience something called ‘shear’ – which is like a twisting or sliding force. We think this allows the carbon atoms to move into place and form Lonsdaleite and regular diamond,” Bradby said.
Lonsdaleite was named after crystallographer Dame Kathleen Lonsdale, who was the first woman elected as a Fellow to the Royal Society.https://www.australianmining.com.au/news/lab-made-diamonds-show-drilling-potential/