What are Laboratory Grown or LAB Diamonds ?

HPHT Method for Growing Laboratory-Grown Diamonds

The High Pressure High Temperature (HPHT) method is a widely used technique for producing synthetic diamonds. This process involves the use of massive presses that can weigh several hundred tons, combined with extremely high temperatures to replicate the natural conditions under which diamonds form. During this process, carbon in the form of graphite is subjected to intense heat and stabilizing pressure, along with a metal catalyst, for a specific duration. The metal acts as a solvent for the graphite and facilitates crystal growth.

To create colored HPHT synthetic diamonds, the as-grown diamond crystals may undergo additional treatments to induce color changes, similar to how natural diamonds are enhanced.

CVD Method for Growing Laboratory-Grown Diamonds

The Chemical Vapor Deposition (CVD) method, developed in the 1980s, is another popular technique for creating synthetic diamonds. This process resembles how frost forms on a window when water vapor condenses in the air. In CVD, diamond crystals are generated from carbon-containing gases in a vacuum chamber, without the need for high pressure.

The CVD process involves mixing gases—typically methane and hydrogen—inside a heated vacuum chamber. The resulting chemical reactions deposit synthetic diamond layers onto a diamond substrate, creating gem-quality diamonds.

Key Differences Between Natural Diamonds and Laboratory-Grown Diamonds

Origin

The primary distinction between natural mined diamonds and laboratory-grown diamonds lies in their origin. Natural diamonds are formed over millions of years deep within the Earth’s mantle under extreme heat and pressure, while laboratory-grown diamonds are created in controlled environments.

Cost

Laboratory-grown diamonds are generally more affordable than their natural counterparts because they bypass the costly mining and extraction processes associated with natural diamonds.

Clarity

Laboratory-grown diamonds tend to have more consistent clarity, as they are cultivated under controlled conditions. In contrast, natural diamonds may contain inclusions or blemishes that affect their clarity and overall value.

Size and Color

Laboratory-grown diamonds can be produced in larger sizes and a wider array of colors, offering options that may be rare or unavailable in natural diamonds.

Environmental Impact

The environmental footprint of laboratory-grown diamonds is often considered lower than that of natural mined diamonds, as diamond mining can significantly impact ecosystems.

Rarity and Value

Despite their similarities, natural diamonds are still regarded as rarer and more valuable due to their historical significance and cultural value.

Ultimately, the choice between a natural mined diamond and a laboratory-grown diamond often depends on personal preferences and priorities, including budget, environmental concerns, and the desire for a unique stone.

Identical Properties

Both natural mined diamonds and laboratory-grown diamonds share identical chemical and physical properties, making them virtually indistinguishable. They can both be certified and graded by independent gemological laboratories based on the same criteria.

Laboratory-grown diamonds are also known by various terms, such as laboratory-created diamonds, cultured diamonds, and synthetic diamonds. These man-made diamonds can be optically and chemically identical to natural diamonds.

Gem-quality synthetic diamonds predominantly exhibit cubic and octahedral forms. While impurities were more common in earlier synthetic diamonds, advancements in technology have led to significant improvements in the quality of rough diamond crystals.

Identification of Laboratory-Grown Diamonds

Although laboratory-grown diamonds share a similar structure and chemical properties with natural diamonds, they can be identified through differences in atomic structure and trace impurities from their unique growth environments.

Color zoning, inclusions, fluorescence, and other characteristics can serve as visual indicators using standard gemological techniques. However, conclusive identification often requires advanced equipment and trained technicians in a laboratory setting.

The DCLA certifies synthetic diamonds, and any laboratory certifying these stones must clearly indicate on the certificate that the diamond is a laboratory-created, synthetic diamond.

Conclusion

Currently, the two primary methods for growing gem-quality synthetic diamonds are the High Pressure High Temperature (HPHT) method and the Chemical Vapor Deposition (CVD) method. Understanding these processes and their distinctions is essential for consumers looking to make informed choices about their diamond purchases.