Trinity Peng - August 2, 2023
How are Lab Grown Diamonds Made?
Lab-grown diamonds are typically produced using two main methods: High Pressure High Temperature (HPHT) and Chemical Vapor Deposition (CVD). Both processes create diamonds with the same chemical composition and crystal structure as natural diamonds, but they are made in controlled laboratory environments instead of being mined from the Earth.
High Pressure High Temperature (HPHT) Method
In the HPHT method, a small diamond seed crystal is placed in a growth cell along with carbon source material. The cell is then subjected to extreme heat (1300-1600 °C) and pressure conditions (870,000 pounds per square inch), mimicking the natural processes that form diamonds deep within the Earth's mantle. The high pressure and temperature cause the carbon atoms in the growth cell to bond together and form a diamond around the seed crystal. Over time, the diamond grows layer by layer, taking several weeks to several months, depending on the desired size of the diamond. Once this process is complete, the lab grown crystal is then cut and polished by a diamond cutter.
Chemical Vapor Deposition (CVD) Method
In the CVD method, a diamond seed is placed in a vacuum chamber, and a mixture of carbon-containing gasses (such as methane) is introduced. The gasses are then activated, typically by using microwave energy, which breaks down the carbon molecules and allows carbon atoms to accumulate on the diamond seed, layer by layer. Crystallization occurs over a period of weeks, and several crystals grow at the same time. Diamonds are removed every few days to have the top surface polished to remove any non-diamond carbon before being put back in to grow. Each batch of diamonds may require several stop/start cycles, and the entire growth process can take three or four weeks. After the synthetic diamond crystals are removed, they are ready to be cut and polished into the final product.
Why choose lab grown diamonds?
Cost-Effectiveness: Lab grown diamonds tend to be less expensive than natural diamonds of similar quality, allowing consumers to get a larger or higher-quality stone for the same budget.
Appearance: Lab grown diamonds are virtually identical to natural diamonds in terms of their chemical, physical, and optical properties. To the naked eye, they look indistinguishable from natural diamonds.
Sustainability: Lab grown diamonds are considered more sustainable and eco-friendly as they do not require mining, which can have environmental impacts.
Conflict-Free: Lab grown diamonds are inherently conflict-free since they are created in controlled laboratory environments, reducing the risk of supporting unethical practices associated with some natural diamond mining operations.
Source: GIA