What is the difference between synthetic diamonds and natural diamonds?

Because of its cultural connotation of eternal and pure love, diamonds are highly sought after by couples.

A small percentage of diamonds on the market today are synthetic diamonds that look almost identical to natural diamonds, but vary widely in value. Today, the publisher will detail the difference between synthetic and natural diamonds.

In fact, the idea of man-made diamonds arose as early as the late 18th century, when it was known that both diamond and graphite were made of carbon.

These man-made diamonds are technically called synthetic diamonds, and are commonly referred to in the marketplace as "lab-grown" or "grown diamonds."

Below, we will first introduce two mainstream synthetic diamonds.

High Temperature High Pressure (HTHP) Synthetic Diamonds

HPHT is a method of producing synthetic diamonds by simulating the environment in which diamonds form in nature. The raw material used is graphite, supplemented by metal catalyst, and put into a large-tonnage hydraulic press with a heating system to generate.

Because the standard and pressure method of hydraulic press molds can affect the growth of diamonds, the shape of synthetic rough diamonds produced by this method is different from natural rough diamonds.

But unfortunately, what we see are generally cut diamonds. At this time, even a sharp-eyed expert can do nothing without the instrument. After all, synthetic diamonds and natural diamonds are identical in appearance.

Chemical Vapor Deposition (CVD) Synthetic Diamonds

The raw materials used in the method are methane and hydrogen, and the carbon atoms in the methane fall on the diamond film to form synthetic diamonds in an environment of high temperature and low pressure.

The rough formed by this method is usually plate-shaped, completely different from natural rough diamond.

Unfortunately, cut CVD synthetic diamonds look exactly like natural diamonds, making it difficult to tell them apart.

Next, we will introduce the difference between synthetic diamonds and natural diamonds from a professional point of view.

No matter how similar synthetic and natural diamonds are in appearance, a professional gemologist can identify the optical and physical properties that differ between the two with the help of specialized testing equipment.

(1) Visible light absorption spectrum

Synthetic diamond: No absorption line at 415 nm at room temperature.

Natural diamonds: Most have absorption lines at 415 nm.

(2) UV fluorescence

Synthetic diamonds: generally do not fluoresce at long wavelengths.

Natural diamonds: mostly blue-white fluorescence at long wavelengths, weak or inert at short wavelengths.

(3) UV fluorescence luminescence image

Synthetic diamonds: The luminescence images of HPHT synthetic diamonds often have hourglass-shaped growth lines, and CVD synthetic diamonds can see layered growth lines.

Natural diamonds: Occasional annular growth patterns.

According to the relevant regulations in GB/T16552 "Names of Jewelry and Jade":

The name of the natural gemstone directly uses the basic name of the natural gemstone or its mineral name, without adding the word "natural", so the natural diamond will not add the word "natural" to the prefix, and it is directly named as the "diamond" identification certificate;

The name of synthetic gemstones should be prefixed with the word "synthetic" before the basic name of the corresponding natural jewelry and jade, so if it is a synthetic diamond, the word "synthetic" must be prefixed with the word "synthetic", that is, the identification certificate should be prefixed with the word "synthetic". The word "Synthetic Diamond" is displayed.

Finally, I remind everyone that if you do not have professional experience, you should ask the merchant for a professional gem identification certificate when purchasing diamonds to avoid losses.