HPHT represents high pressure and high temperature. During the process of creating a lab-grown diamond, a diamond seed is placed inside a large press that produces high pressures exceeding 870,000 pounds per square inch at temperatures ranging from 1300-1600°C. A metallic flux containing a high-purity carbon source is melted during the process, and the carbon atoms dissolve within it. As the carbon atoms crystallize around the seed crystal, a synthetic diamond is formed. Once grown, the lab-grown diamond is cut and polished before being set in jewelry.
The process of growing HPHT diamonds is conducted in a small capsule contained within an apparatus capable of producing extremely high-pressure conditions. The capsule contains a starting carbon material, such as graphite, that dissolves in a molten flux composed of metals like iron (Fe), nickel (Ni), or cobalt (Co). This unique mixture of materials lowers the pressure and temperature required for diamond growth.
As the carbon material migrates through the flux, it moves towards the cooler diamond seed where it crystallizes to form a synthetic diamond crystal. Crystal growth occurs over several days to weeks until one or multiple crystals have formed. This process involves careful monitoring of temperature and pressure levels to ensure optimal growth conditions for the diamonds.
Although natural diamonds usually take the form of octahedrons, synthetic diamonds produced through high-pressure and high-temperature (HPHT) processes tend to have both cubic and octahedral faces. As a result of these different shapes, the growth patterns within natural and HPHT synthetic diamond crystals can be vastly distinct. It is through these growth patterns that one can reliably distinguish between natural and synthetic diamond crystals.
Synthetic gemstones that have been cut and polished may display unique color patterns, areas of fluorescence, and visible graining. These characteristics are attributable to the cross-shaped growth-sector structure of the crystals during their formation. Additionally, these synthetic gems may contain inclusions of dark flux-metal. In certain instances, these materials may exhibit phosphorescence, continuing to glow after being exposed to ultraviolet light even when the light source is no longer present.
Producing colorless synthetic diamonds through the HPHT method was once a difficult task due to the presence of nitrogen, which causes diamonds to turn yellow. Therefore, it was necessary to prevent nitrogen from entering the growth environment. Furthermore, creating high-purity colorless diamonds required more precise control over growth temperature and pressure conditions as well as longer growth times. However, thanks to recent technological advancements, laboratories are now capable of producing colorless diamond crystals that can be cut and polished to sizes of 10 carats or larger.
By incorporating boron during the growth process, synthetic diamonds with blue hues can be produced. While other colors, such as pink and red, can be achieved through post-growth treatment involving heating and radiation, they are not as frequently developed.
Natural diamonds were created billions of years ago at depths of approximately 150 km below the earth’s surface. The HPHT (High-Pressure High Temperature) process mimics the conditions necessary for diamond growth on the earth. This process is one of the primary methods used for creating synthetic diamonds.
In the 1990s, scientists began exploring ways to alter diamond color using HPHT technology. This led to the development of high-pressure, high-temperature (HPHT) color treatments for diamonds. HPHT-treated diamonds are natural and mined, but they undergo the HPHT process to enhance their color.
This treatment can permanently change the color of brownish diamonds into colorless gems. It can also transform yellowish-looking diamonds into fancy-colored stones. As the original stones were brownish or yellowish, the resulting treated diamonds are less expensive than untreated ones. Choosing an HPHT-treated diamond is a great option as it offers the beauty of a natural diamond at a fraction of the cost.
HPHT diamonds are a popular choice for use in fine jewelry, where they can be paired with various metals such as gold, platinum, and silver. These diamonds are readily available at wholesale prices and are certified for purity and clarity, making them a reliable choice for jewelry manufacturers who incorporate them into their designs.
As HPHT diamonds undergo a certification process to ensure their quality, purity, and clarity, they make an excellent choice for inclusion in high-end jewelry pieces. As a result, manufacturers often rely on these diamonds when creating spectacular ornamentation.
Affordable pricing is a significant advantage of HPHT diamonds over natural stones, which can be quite expensive due to the lengthy mining process, supply chain, and middleman commissions involved. As HPHT diamonds come directly from the laboratory, they are an excellent choice for those seeking affordable diamond options.
HPHT diamonds are lab-grown and come with certification from reputable quality-checking labs such as GIA, CGI, and others. When you purchase an HPHT diamond with certification, you can be assured of its authenticity and quality. This certification adds an extra layer of assurance that the diamond you’re purchasing is genuine and has undergone the necessary quality checks.
Natural diamonds damage the minerals, lands, and forests as well due to lots of cutting trees and blasting for mining. There is earth damage that can directly affect climate change. This lab-grown HPHT diamond is completely environmentally friendly.