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About lab-grown diamonds

Q. Are lab-grown diamonds different from synthetic diamonds?

Synthetic diamonds and lab-grown diamonds basically represent the same thing. There are other terms such as "artificial diamond", "artificial diamond", and "cultured diamond", but they are basically the same. Unlike simulants (which look like diamonds) such as cubic zirconia, moissanite, and crystal, they are "real diamonds" with the same chemical properties as natural diamonds.

Q. Which name is correct, lab-grown diamond or synthetic diamond?

Neither is wrong. However, because the word “synthetic” possible to give the impression of being fake, it is common to use lab-grown diamonds worldwide. The world's authoritative diamond appraisal institutions such as "GIA", "IGI", and "HRD" all use the name of Laboratory Grown Diamond, and most of the companies and brands use the Lab Grown Diamond name.

Q. It's possible to distinguish lab-grown diamonds from natural diamonds by naked eyes?

Since both lab-grown diamonds and natural diamonds are the same substance in which carbon is crystallized, it is basically impossible to distinguish them by visual observation (naked eye, loupe, microscope, etc.). However, in rare cases, both lab-grown diamonds and natural diamonds have some characteristics, and it is possible to distinguish them by observing their appearance based on the type and shape of inclusions. However, for high-quality diamonds, even a professional diamond grader cannot tell the difference between a lab-grown diamonds and a natural diamonds.

Q. How to distinguish lab-grown diamonds?

Unlike lab-grown diamonds, more than 98% of natural diamonds contain nitrogen as an impurity, which is used for rough sorting. Nitrogen-containing diamonds do not transmit ultraviolet rays around 250 nm, while those that do not contain nitrogen do. Therefore, it is possible to distinguish the presence or absence of nitrogen content by ultraviolet transmission. Nitrogen-containing colorless diamonds are 100% natural diamonds. Nitrogen-free diamonds can be rare natural diamonds or lab-grown diamonds. Anyhow it is possible to finally determine whether a diamond is a natural diamond or a lab-grown diamond but by inspection using multiple inspection equipment such as FT-IR (infrared spectrometer) and observation under ultra-short-wave ultraviolet environment.

Q. Is it possible to distinguish with a simple diamond checker?

A simple diamond checker on the market is designed to judge whether a diamond is a diamond or a simulant based on the thermal conductivity of the diamond. Natural diamonds and lab-grown diamonds are the same material and have the same thermal conductivity, so it cannot be distinguished by commercially available diamond checkers. In addition, since the thermal conductivity of diamond and moissanite is very close, diamonds are possibley rarely labeled as moissanite, but diamonds and moissanite are distinguished by a combination of several tests even at gem lab. It is dangerous to believe easily just because it is displayed as moissanite on a commercially available diamond checker.

Q. Are all lab-grown diamonds Type 2?

All "colorless" lab-grown diamonds are Type 2. All lab-grown diamonds with colors above J and K are Type 2. Yellowish lab-grown diamonds are classified as Type 1b, while blue lab-grown diamonds are classified as Type 2b because they contain boron.

Q. Which makes a more beautiful lab-grown diamond, CVD or HPHT?

There is no absolute advantage over one or the other. High-quality lab-grown diamonds grown using advanced technology have almost no superiority or inferiority, whether they are CVD or HPHT. However, depending on the size, shape, and grade of diamonds, there are pros and cons for production efficiency, so depending on the category, one of the growth methods may have a large market volume or a high price advantage. On the other hand, lower-quality diamonds may have their own characteristic inclusions, and may also show the color of the diamond itself or interference patterns under certain light sources. Also, while all colorless CVD diamonds are classified as Type 2a (contains no impurities), some HPHT may be classified as Type 2b (contains boron as an impurity).

Q. Is it true that lab-grown diamonds have no asset value?

The market for lab-grown diamonds has been established relatively recently, and there is no secondary distribution market yet, so it is sometimes said that there is no asset value. As the market for lab-grown diamonds expands, it is believed that a secondary distribution market will be formed in the future. Lab-grown diamonds, which currently do not have a secondary market, also have the advantage that almost all diamonds sold are virgin diamonds. In addition, even natural diamonds that can be called asset value are limited to particularly large diamonds and fancy color diamonds with high rarity. If you try to sell a general diamond purchased at a regular jewelry store, it will be about 30% of the purchase price. Considering that equivalent lab-grown diamonds can be purchased for about 1/4 of the price of natural diamonds, the cost performance of lab-grown diamonds surpasses natural diamonds even if consider about terms of natural diamond's cashability. The value of both natural and lab-grown diamonds, except those specifically sold as asset value, is determined by the wearer as a piece of jewelry, or by the psychology of the giver and receiver of the gift. Since it is a physical thing, it is considered that the liquidity is only secondary.

About dealings

Q. Can anyone buy from Pure Diamond?

Pure Diamond is a wholesale company. Therefore, we limit sales to corporations and sole proprietors. General customers can purchase from our affiliated AFRICA DIAMONDS stores or the EC site PRIORITY DIAMOND. You can see each site from the link at the bottom of the top page.

Q. Is it possible to purchase from 1 item?

Diamonds other than melee size can be purchased from one piece. If items that are not in stock in Japan will be ordered from overseas, but in that case, international shipping cost may be charged. In addition, we may be able to offer better conditions for continuous deals and/or large deals. Please contact us for details.

Q. Which gem lab do you use for the certificate?

Most lab-grown diamonds are accompanied by an internationally trusted IGI certificate based in Antwerp, Belgium. Some of our products are also provided by Belgium's HRD, America's GIA, and GCAL, all of which are internationally reliable top-level gem labs.

Q. Is custom cut possible?

Yes, is possible. The minimum lot and amount are set differently depending on the size, grade, shape, etc. Please contact us for details.

Q. Is it possible to specify CVD or HPHT?

Yes, it is possible to specify CVD or HPHT for lab-grown diamonds other than melee size. However, CVD and HPHT have different size and grade production efficiency, so if you specify the growth method, it may affect the price and supply stability.

Q. Do you have a certificate of origin?

Carbon-neutral lab-grown diamonds are supplied with a certificate of origin. Please contact us for details as there are limits on size, grade, supply volume, etc.

Q. Can I purchase melee size diamonds starting from 1 stone? Is it possible to specify the size?

For melee-sized lab-grown diamonds, we ask that you purchase by carat, not by quantity. Regarding the size, it is possible to specify the diameter. (Example: 2.00mm - 2.10mm for 5 carats, etc.)

Q. Is it possible to purchase As-Grown CVDs?

Is possible. Since it will be supplied by some producers, the range of sizes, shapes, grades, etc. will be limited. Please contact us for details.

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