The Indian Institute of Technology, Madras (IIT-M), has begun research into lab-grown diamonds (LGD) at the institute, which now intends to set up a National Centre for Lab-Grown Diamonds. IIT-M will primarily concern itself with research into developing technologies for producing seeds in India, as per a report in The Hindu.
The production of these synthetic diamonds starts with ‘seeds’. MS Ramachandra Rao of the Department of Physics, IIT-M, said the two processes of making LGD — high pressure, high temperature and chemical vapour deposition — start with the seeds, which are diamond ‘Type IIa’ crystals, which have no nitrogen or boron impurities. Only 2 per cent of naturally occurring diamonds are Type IIa and are, therefore, very expensive. Only a few companies in the world have the know-how to produce mother seeds.
There is no known source of high-quality mother seeds or related technology in India. Currently, it is being imported from other countries to grow a good-quality diamond. In the HPHT method, seeds are exposed along with carbon powder and a catalyst to temperatures of the order of 1,600 degrees Celsius and pressures of about six Giga Pascals. The CVD method involves breaking down molecules of a carbon-rich gas, such as methane, into carbon and hydrogen atoms in a sealed chamber at sub-atmospheric pressures and temperatures of about 1,100 degrees Celsius. The gas is then deposited onto the seeds to produce a square-shaped diamond crystal.
LGD beat natural diamonds in purity. “Only 2 per cent of naturally occurring diamonds are defect-free whereas we can grow good quality defect-free diamonds in laboratories, consistently,” said Rao.
Emerging technologies such as high-power electronics, 5G/6G base-station electronics, sensors, magnetometry and quantum computing, need high-purity diamonds which can only be grown in a lab using CVD and HPHT processes.
As for costs, “LGD of less than one-carat size is 3-4 times cheaper than natural diamond,” Rao said.
Aruna Gaitonde, Editor in Chief of The Asian Bureau, Rough&Polished
The production of these synthetic diamonds starts with ‘seeds’. MS Ramachandra Rao of the Department of Physics, IIT-M, said the two processes of making LGD — high pressure, high temperature and chemical vapour deposition — start with the seeds, which are diamond ‘Type IIa’ crystals, which have no nitrogen or boron impurities. Only 2 per cent of naturally occurring diamonds are Type IIa and are, therefore, very expensive. Only a few companies in the world have the know-how to produce mother seeds.
There is no known source of high-quality mother seeds or related technology in India. Currently, it is being imported from other countries to grow a good-quality diamond. In the HPHT method, seeds are exposed along with carbon powder and a catalyst to temperatures of the order of 1,600 degrees Celsius and pressures of about six Giga Pascals. The CVD method involves breaking down molecules of a carbon-rich gas, such as methane, into carbon and hydrogen atoms in a sealed chamber at sub-atmospheric pressures and temperatures of about 1,100 degrees Celsius. The gas is then deposited onto the seeds to produce a square-shaped diamond crystal.
LGD beat natural diamonds in purity. “Only 2 per cent of naturally occurring diamonds are defect-free whereas we can grow good quality defect-free diamonds in laboratories, consistently,” said Rao.
Emerging technologies such as high-power electronics, 5G/6G base-station electronics, sensors, magnetometry and quantum computing, need high-purity diamonds which can only be grown in a lab using CVD and HPHT processes.
As for costs, “LGD of less than one-carat size is 3-4 times cheaper than natural diamond,” Rao said.
Aruna Gaitonde, Editor in Chief of The Asian Bureau, Rough&Polished
