Lab Grown Diamonds

Table of Contents

Context: Prime Minister Narendra Modi presented an exquisite gift to US First Lady Jill Biden – a lab-grown 7.5-carat green diamond – on his state visit to the United States.

What are Lab-Grown Diamonds (LGDs)?

LGDs, also known as synthetic diamonds or cultured diamonds, are diamonds that are created in a laboratory environment rather than being formed naturally deep within the Earth’s crust.
The world’s first-ever LGD was created in 1954 by scientists working at a General Electric research laboratory in New York.
These diamonds have the same chemical composition, crystal structure, and physical properties as natural diamonds.
However, LDGs are different from diamond simulants, which are materials that resemble the appearance of diamonds but have different chemical compositions and physical properties.
- Unlike lab-grown diamonds, simulants do not contain carbon atoms arranged in a crystal lattice structure like natural or synthetic diamonds.
- Examples of diamond stimulants include Moissanite, Cubic Zirconia (CZ), White Sapphire, YAG, etc.

How LDGs are Produced?

Lab-grown diamonds are produced by two primary methods:

High-Pressure High-Temperature (HPHT):
- This method involves placing a small diamond seed in a chamber and applying high pressure and temperature to simulate the natural conditions under which diamonds form in the Earth’s mantle.
  - Diamond seeds are small pieces of natural or synthetic diamond material that serve as the foundation for the growth of larger diamonds in a laboratory setting.
  - Usually, graphite is used as the “diamond seed” and when subjected to these extreme conditions.
- Carbon atoms from a carbon-rich source are then dissolved and crystallize around the seed, gradually growing into a larger diamond.
Chemical Vapor Deposition (CVD):
- In this method, a diamond seed is placed in a chamber filled with carbon-rich gases.
- These gases are then ionized, breaking down the molecular bonds and causing carbon atoms to separate and deposit onto the diamond seed, layer by layer.
- Over time, the layers build up, resulting in the growth of a complete diamond.

Characteristics and Applications of LDGs

LGDs have basic properties similar to natural diamonds, including their optical dispersion, which provides them with the signature diamond sheen.
However, since they are created in controlled environments, many of their properties can be enhanced for various purposes.
LGDs are most often used for industrial purposes, in machines and tools.
- Their hardness and extra strength make them ideal for use as cutters.
- Pure synthetic diamonds have high thermal conductivity, but negligible electrical conductivity.
- This combination is invaluable for electronics where such diamonds can be used as a heat spreader for high-power laser diodes, laser arrays and high-power transistors.

Advantages of LDGs

Declining natural reserves: As the Earth’s reserves of natural diamonds are getting depleted, LGDs are slowly replacing the prized gemstone in the jewellery industry.
Low environmental footprint: The environmental footprint of a diamond grown in a laboratory is much lesser than that of a naturally occurring diamond.
Lower energy consumption: It takes ten times more energy to extract a natural diamond (by open pit mining) from the earth than it takes in creating one above the ground.
Similar features: Just like natural diamonds, since LGDs also undergo similar processes of polishing and cutting, they have a similar lustre. Furthermore, lab-grown diamonds are indistinguishable from natural diamonds to the naked eye and even to many gemological tests.

Union Budget 2023-24’s Push for LDGs

Reducing custom duties: The 2023 Union Budget promises to reduce the basic customs duty on seeds used in the manufacture of lab-grown diamonds in a bid to popularize their production in India— the duty on seeds for rough LGDs will be reduced from 5% to nil.
Research grant: A five-year research grant will also be provided to one of the Indian Institute of Technologies (IITs) for research and development in the field of LGDs.
New tariff lines: A proposal for the creation of new tariff lines to help in better identification of a number of products, including synthetic diamonds has also been made.