Learn About Lab Grown Diamonds
What are lab-grown diamonds?
Lab-grown diamonds (also known as lab-created diamonds, man-made diamonds, engineered diamonds, and cultured diamonds) are grown in highly controlled laboratory environments using advanced technological processes that duplicate the conditions under which diamonds naturally develop when they form in the mantle, beneath the Earth’s crust. These lab-created diamonds consist of actual carbon atoms arranged in the characteristic diamond crystal structure. Since they are made of the same material as natural diamonds, they exhibit the same optical and chemical properties.
Did you know that lab-grown diamonds are not the same as imitations or simulants? They have all the same properties as mined diamonds, including physical, chemical, and optical properties. The only difference between the two is their origin. It’s fascinating to think about how technology has advanced to be able to create diamonds in a lab that are almost indistinguishable from those found in nature. In fact, you cannot tell the difference with the naked eye; special equipment is required to test whether a diamond is lab-made or natural.
The journey of these diamonds begins in a lab using methods such as High-Pressure High-Temperature (HPHT) and Chemical Vapor Deposition (CVD), which recreate the conditions under which diamonds naturally form deep within the Earth’s mantle. These methods allow labs to produce exquisite rough diamonds in as little as a few weeks, compared to the billions of years it takes to create a natural diamond.
How Are Lab-Grown Diamonds Made?
Lab-grown diamonds are created from tiny carbon seeds of pre-existing diamonds. Using advanced technology, scientists replicate the natural diamond formation process through methods such as High-Pressure High Temperature (HPHT) and Chemical Vapor Deposition (CVD).
Over the course of six to ten weeks, a rough diamond is formed, which is then cut, polished, and set into jewelry like earrings, necklaces, or bracelets.
High-Pressure High Temperature (HPHT) Method
The HPHT method simulates the extreme conditions found deep within the earth where natural diamonds form.
This process involves a large machine applying immense pressure, more than 870,000 pounds per square inch, and extreme temperatures ranging from 1300 to 1600 degrees Celsius to a carbon source.
Under these conditions, carbon atoms crystallize to form a diamond around a small diamond seed.
Chemical Vapor Deposition (CVD) Method
The CVD method involves placing diamond seed crystals in a vacuum chamber filled with a carbon-containing gas, such as methane, and hydrogen. The chamber is heated to about 900-1200°C. A microwave beam or another energy source breaks down the gas molecules, causing carbon atoms to precipitate out of a plasma cloud and deposit onto the seed crystal. This results in the growth of diamond layers over a period of weeks.
In greater detail, CVD diamond growth takes place inside a vacuum chamber filled with a hydrogen and carbon-containing gas mixture. The energy source, like a microwave beam, splits the gas molecules, and the carbon atoms diffuse towards the colder diamond seed plates. Crystallization occurs over several weeks, during which multiple crystals can grow simultaneously, depending on the size of the chamber and the number of seed plates. The process may require several cycles of growth and polishing. Diamonds are periodically removed from the chamber to polish away non-diamond carbon before being returned to grow further. This ensures the purity and quality of the diamond.
Post-Growth Treatment
CVD-grown diamonds often exhibit a brown color that can be removed through heat treatment before cutting and polishing. The final product is a high-quality diamond that is chemically, physically, and optically identical to natural diamonds.
Lab-grown diamonds, whether produced through HPHT or CVD methods, are indistinguishable from natural diamonds to the naked eye. Both methods continue to improve, allowing for the creation of larger diamonds with better color and clarity. These advancements make lab-grown diamonds a compelling alternative to natural diamonds, offering the same beauty and durability at a potentially lower cost and with fewer environmental and ethical concerns.