Temperature and pressure are also two key factors in the manufacture of crystals, which are made in ceramic vessels rather than underground, where water pressure provides high pressure and electricity generates high temperatures, causing carbon to form crystals around seed crystals of 1 mm in diameter, made from natural diamonds.
HPHT diamonds are also known as "Type IIa" diamonds, which are characterized by their lack of nitrogen impurities. This results in a very high level of purity and exceptional clarity compared to other types of synthetic diamonds or natural diamonds.
One of the major advantages of HPHT diamonds is their ability to produce large, high-quality diamonds at a lower cost compared to mining natural diamonds. They are widely used in industrial applications such as cutting tools and drilling equipment. HPHT diamonds also have a growing popularity as gemstones in fine jewelry.
However, it's important to note that because HPHT diamonds share many of the same visual characteristics as natural diamonds, they can be difficult to differentiate from genuine, untreated diamonds without specialized testing techniques. As a result, it's important to purchase HPHT diamonds from reputable dealers who can provide proper certification and authentication.