news

CVD VS HPHT - WHICH ONE SHOULD YOU GO FOR?

Laboratory grown diamonds have become a popular subject of conversation across the country as a result of their growing success. Most customers know that a laboratory grown diamond is created using a 'seed' in a laboratory that mimics the mechanism of diamond formation, but they do not know that there are two other processes.

Experiments in processing laboratory diamonds began in the 1950s, but the gems were too small and of bad quality due to technological constraints of that period, making laboratory diamonds used only for industrial purposes. The laboratory diamond has evolved into a gem-quality diamond that can be used in jewellery manufacturing as time, technology, and human imagination have advanced.

The standard diamond treatment process is known as the HPHT (High Pressure High Temperature Diamond) method, which uses graphite as the raw material and adds special catalysts such as iron, cobalt, and nickel to form carbon crystals over a long period of time under high temperature and pressure (about 50,000 bar, 1200°C-2000°C), resulting in what we call HPHT diamond.

A more recent manufacturing process is CVD (Chemical Vapour Deposition Diamond) which uses methane (CH4) and hydrogen (H2) as raw materials to grow carbon crystals under vacuum and high temperature (about 1000°C-5000°C ion plasma ball) over a long period of time.

Another result of the HPHT method of producing high clarity colourless diamonds with other metals is that the final colour has other colours, which makes the manufacturing of high clarity colourless diamonds relatively difficult. CVD diamonds do not have metallic inclusions, but instead have dark graphite or other mineral inclusions, which are formed during the diamond's growth and, contrary to metallic inclusions; they do not have a metallic lustre, this allows the CVD process to produce high visibility colourless diamonds.

Institutions such as IGI and GIA will measure them using specialised equipment and provide certificates that state the technique used to create the laboratory diamond, therefore the certificate guarantee that the laboratory diamond is as authentic as a natural diamond regardless of the process used.

SHAN's laboratory diamond jewellery is certified by IGI. Therefore, you can confidently buy beautiful jewellery from the online store right now!
Back to blog