CVD stands for chemical vapor deposition. Lab grown diamond seeds are loaded into a CVD reactor. Then, a mix of gasses containing carbon is added at a very low pressure. Additional microwaves are added to heat the gases and generate a plasma. When the temperatures climb over several thousand degrees, the gas molecules break apart and carbon atoms bond to the seeds, growing them one layer at a time. With our ground-breaking technology, we can grow lab-created diamonds in a few weeks. In theory, there is no limit to the size of a lab-grown diamond. The longer they grow the bigger they get, but currently the biggest lab-diamond ever made is 155 carats
HOW ARE LAB-CREATED DIAMONDS CERTIFIED AND GRADED? Lab-created diamonds are graded and certified using the same process as mined diamonds. Diamonds are sent to a gem lab that specializes in grading diamonds. The majority of these labs grade using the 4c’s (cut, clarity, color, and carat — more on those later), however, a select few use their own criteria. The most popular diamond certification labs are: Gemological Institute of America (GIA) International Gemological Institute (IGI) European Gemelogical Labratory (EGL)
The lab created diamond grading process is roughly the same for all of the certification labs. Each lab created diamond is graded independently by several gemologists at the lab. The individual grades are compiled and analyzed to determine the final grade. This process is designed to provide each lab creased diamond with an unbiased grade. However, it’s not uncommon for a lab created diamond to get a different grade, not only from a different lab but from the same lab if sent back for a second grading. A diamond is evaluated using the 4c’s – cut, clarity, color, and carat. Basically, they judge the diamond on how well it has been cut down from its raw form into a jewel, how flawless and clear it is, and its size. Below you’ll find an explanation of each category and the different measurements used for each.
The Carat weight to Millimeter Converter is a professional tool that helps to approximately determine the diameter of diamond according to its weight. The converter considers the shape of the stone, providing measurements for Round Brilliants, Cushion Cuts, Pear Shapes, Emerald Cuts, Oval Cuts, Princess Cuts, Heart Shapes, Marquise Cuts, Asscher Cuts and Radiant Cuts.