Man-Made Diamonds Lab Grown

What Are Man Made Diamonds?

Lab created diamonds, also known as lab-grown diamonds and synthetic diamonds, are pure carbon diamonds grown in highly-controlled laboratory conditions that simulate the Earth’s natural growing process, above ground. The results yield real diamonds that are physically, chemically and optically identical to mined diamonds.

While people have experimented with diamond growing technology for more than a century, it has only been in the last decade that we’ve been able to perfect the science of creating gem-quality man made diamonds in a modern-day lab. With today’s technological advances, we are growing diamonds that are free of conflict and superior in every way to earth-mined diamonds.

 

 

How Are Lab Created Diamonds Grown?

Man made diamonds are created by placing a ‘seed’ into a chamber of heat and pressure. This chamber mimics the natural growing process. Crystallization occurs allowing the diamond to mature within six to ten weeks. It is then cut, polished and graded by the same world-renowned labs that certify earth-mined diamonds. The following combination of techniques are most commonly used by laboratories:

 

Chemical Vapor Deposition (CVD)

Chemical Vapor Deposition, or CVD, is a process used to create gem-grade diamonds as well as optics and semiconductors. The CVD process uses ultra-pure carbon-rich gasses in a controlled chamber. Carbon based gasses, such as methane, are heated until they break apart allowing the carbon atoms within the gas to separate. These tiny carbon atoms fall onto a diamond substrate and build up layers resulting in a rough diamond crystal. This process takes between six to ten weeks and yields gem-grade, Type lla diamonds.

In recent years, CVD research has gained popularity and now modified versions of CVD are being used. These processes differ in the means by which chemical reactions are initiated. Some of these variations include:

  • Low-pressure CVD (LPCVD)
  • Ultrahigh vacuum CVD (UHVCVD)
  • Plasma-enhanced chemical vapor deposition (PECVD)
  • Microwave Plasma Vapor Deposition (MPCVD)

 

 

High-Pressure High-Temperature (HPHT)

High-Pressure High-Temperature, or HPHT, recreates a diamond's natural growing environment found deep within the Earth. The machines used have the ability to build up the pressure of almost 60,000 atmospheres and temperature of 2,500 degrees Celsius.

The growth cell contains all the elements needed to grow a diamond, including a seed, highly refined graphite and a catalyst mixture consisting of metals and powders. The cell is placed in the center of the HPHT chamber. Consistent temperatures reaching 1,300 degrees Celsius and more than 50,000 atmospheres of pressure are applied. The catalysts inside the cell are the first to react to the added heat and pressure and change from solid to molten form.

The molten catalyst solution causes the graphite within the cell to dissolve. Once all the required conditions are met, the cooling process begins. This process takes place over several days and allows the carbon atoms to build upon the seed. The cell is removed from the HPHT machine once the growth cycle is complete. The new rough diamond is extracted and cleaned in preparation for final cutting and polishing.

The entire HPHT growing process requires an incredibly controlled environment to produce a gem-quality diamond. Any shift or change during growth can cause the diamond to stop growing or can create inclusions that result in unusable diamonds. Every diamond must complete the entire growth cycle before the machine can be opened. It is only after the HPHT chamber is opened that we can see the finished rough diamond and its color, clarity, and size.

Within the HPHT process, there are three primary tools used to supply the pressure and temperature necessary to produce lab-grown diamonds. These are:

  1. Bars Press - The Bars Press is the most effective tool used for producing gem-quality diamonds. It uses a combination of inner and outer anvils to apply hydraulic pressure to the growth cell.
  2. Belt Press - The Belt Press is the founding technology behind growing diamonds. It can be large and produce several diamonds in only one cycle by using two large anvils that press together to create the necessary pressure. It is capable of producing gem-quality diamonds but is most commonly used to produce diamonds and diamond powder for industrial purposes.
  3. Cubic Press - A Cubic Press can be large in size and uses six separate anvils to create the necessary pressure for diamond crystal growth. It is also used to create diamond powder for industrial purposes.