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Lab Grown Diamond FAQs

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What is a lab grown diamond?

Lab grown diamond is also known as cultured, synthetic, lab-created, man-made, engineered or future diamond.

Lab grown diamonds have the same chemical composition and physical properties as natural diamonds. They are cubic crystals of pure carbon and are definitely real diamonds. The biggest difference between the two is their formation and rarity. Lab grown diamonds are manufactured in a laboratory using sustainable methods (HPHT or CVD), while natural diamonds are naturally formed in the depths of the earth more than a billion years ago. Nonetheless, both exhibit the same dazzling brilliance and fire.

Lab grown diamonds have been around since the 1950s, but the technology at the time could only produce diamond quality for industrial use. Until recent years, the rapid development of technology has caused amazing changes in the quality and price of lab grown diamonds. Now, gem-quality lab grown diamonds can be produced sustainably within a limited time to create more affordable luxury jewelry.

Formation of lab grown diamonds

Gem-quality lab grown diamonds are mainly produced by two methods: High Pressure High Temperature (HPHT) and Chemical Vapor Deposition (CVD).


High Pressure High Temperature (HPHT)

The principle of this method is to simulate the growth conditions of natural diamonds. A diamond seed is placed in a large chamber along with carbon and metal catalysts, then the assembly is compressed and heated to generate high temperatures of 1300–1600°C and pressures of 5–6 GPa (roughly equivalent to the pressure exerted by a commercial jet). Depending on the desired diamond size, HPHT-grown diamonds typically take from a few days to a few weeks to grow. This method usually produces colorless diamond crystals, and also colored diamonds. In addition, HPHT equipment can be used to improve the color of lower-quality natural or lab grown diamonds.


Chemical Vapor Deposition (CVD)

This method uses relatively low pressure and moderate temperature (700°C to 1300°C) to grow diamonds. Carbon-containing gases are pumped into the vacuum chamber, deposited on the diamond seeds and crystallized into synthetic diamonds. The final size of the diamond depends on the growth time, which usually takes 4-6 weeks. The CVD growth process is generally more arduous and time-consuming than HPHT, because the diamond crystals need to be removed several times during the growth process to remove the graphite layer formed around the diamond, otherwise it will not continue to grow into a larger diamond crystal. After CVD-grown diamonds are formed, HPHT treatments are often required to change their color, making them more colorless or giving them fancy colors. Because the up-front equipment cost of the CVD method is lower than that of HPHT, many lab grown diamond manufacturers choose to grow their diamonds with the CVD method.

What is the difference between lab grown diamonds and natural diamonds?

Formation
Both are cubic crystals composed of pure carbon, with the same chemical composition and physical properties, and the same sparkles. But lab grown diamonds are cultured in a laboratory, while natural diamonds are grown naturally deep underground over thousands of years.

Rarity
Lab grown diamonds can be produced sustainably in quantity; but natural diamonds that exist on Earth have been formed over a billion year ago, so they are relatively more rare and precious. This difference in rarity makes lab grown diamonds more price-competitive than natural diamonds of the same size and quality.

Internal Characteristics
Lab grown diamonds and natural diamonds are indistinguishable with naked eyes, magnifying glass or diamond testing pen. But lab grown diamonds have different trace elements, inclusions, and unique growth patterns from natural diamonds, all of which do not affect the diamond's appearance, but do allow laboratories to distinguish between the two types of diamonds.

How can consumers distinguish between lab grown diamonds and natural diamonds?

Lab grown diamonds have the same physical, chemical and optical properties as natural diamonds and are real diamonds. Even an experienced jeweler can hardly tell the difference between the two types of diamonds with the naked eye.

Therefore, the only way to differentiate them is to rely on the diamond grading report issued by authoritative gem laboratories, or the use of specialized high-tech equipments. At present, the world's two major gemological laboratories, GIA and IGI, will engrave the words "LABORATORY-GROWN" or "LABGROWN" as well as the report number to the girdle of the lab grown diamond by laser for identification.

We believe that, no matter buying which type of diamonds, natural diamonds of 0.30ct or above and lab grown diamonds of 0.50ct or above should always come with a highly recognised grading report to give consumers the greatest protection.

How are lab grown diamonds certified and graded?

Lab grown diamonds are graded using the same rigorous standards as natural diamonds. Both GIA and IGI issue lab grown diamond grading reports by evaluating the 4Cs of diamond quality: Carat, Color, Clarity, Cut, and more. <Learn about the 4Cs of diamonds>

The grading report will clearly indicate that the diamond is laboratory grown, and will also reveal that the diamond was produced by High Pressure High Temperature (HPHT) mothod or by Chemical Vapor Deposition (CVD) method. In addition, whether any post-growth treatment detected, or even if the treatment could not be determined will also be stated on the report. GIA's lab grown diamond grading report is only available as electronic copy, while IGI can provide hard copy of the grading report. Both GIA and IGI laser inscribe "LABORATORY-GROWN" or "LABGROWN" plus the report number on the girdle of lab grown diamonds to ensure consumers can be clearly notified that they are buying a lab grown diamond.

Are lab grown diamonds or natural diamonds better?

Lab grown diamonds have the same physical, chemical and optical properties as natural diamonds, and also the same brilliance and sparkles. But lab grown diamonds are more affordable and manufactured in a more environmentally friendly process. They are now an emerging luxury in the market.

Natural diamonds were formed in the Earth mantle more than a billion years ago and are nature's most precious and beautiful creations. Its rarity is unparalleled, and it is the most sought after gem from ancient times to the present. Therefore, natural diamonds have a higher ability to preserve their value.

We believe that both lab grown diamonds and natural diamonds have their own advantages. Customers are recommended to carefully compare the characteristics of the two before making decisions. Make an appointment now for professional consultation to learn about the two types of diamonds.

The use of lab grown diamonds for engagement rings?

Everyone has different considerations when buying an engagement ring. If customers prefer higher 4Cs quality within a limited budget, or would love to go for a more environmentally friendly option. Lab grown diamonds, which have no difference from natural diamonds in appearance, are ideal substitutes for natural diamonds.

As we all know, natural diamonds are expensive. Money saved from buying a lab grown diamond instead of a natural diamond can be used on other wedding expenses or later in life. Although the use of natural diamond rings for engagement has been a widely known tradition, lab grown diamonds have gradually become the choice of more people, especially the younger generation.

But the most important part is to respect the preference of your loved one. This is always a big deal in life, and it's best to know your partner's thought or reach a consensus before buying a lab grown diamond as an engagement ring.

Does a lab grown diamonds preserve its value? Is there any investment potential?

A gem's ability to retain its value depends on its rarity and the cost of repurchasing it.

Lab grown diamonds can be produced sustainably to meet market demand despite its high technical setup requirements. Therefore, it is estimated that the value of lab grown diamonds on the secondary market will be lower. We consider lab grown diamonds to be more for personal use and not recommended for investment.

How are diamond simulants / imitation diamonds different from lab grown diamonds?

Diamond simulants / imitation diamonds (or some self-proclaimed "synthetic diamonds") are generally low-cost mass-produced stones (not even regarded as semi-precious stones), while lab grown diamonds are real diamonds. The two may look similar at first glance, but the chemical and physical properties of a simulant are completely different from a diamond. Simulants do not have the scintillation and optical properties of real diamonds. Also, they will show signs of wear and tarnish from daily wear because they do not have the hardness like diamonds do.

If consumers understand clearly the difference between simulants and real diamonds, there is no problem buying a simulant and it is totally a personal choice. However, there are certain merchants with bad sales practices who abuse the word "diamond" to package or name their low-cost simulants in order to mislead consumers. These merchants claim that their simulants have the same sparkles and brilliance as natural diamonds and are indistinguishable in appearance. In fact, people with basic knowledge of diamonds should be able to differentiate the two with just naked eyes.