What Are the Technologies Involved in Making Synthetic Diamonds?

Diamonds are the toughest substances on the planet. Miners are retrieving them from deep beneath the ground for hundreds of years. Diamonds are naturally-occurring carbon crystals. They are produced by pressure and heat miles under …

Making Synthetic Diamonds

Diamonds are the toughest substances on the planet. Miners are retrieving them from deep beneath the ground for hundreds of years. Diamonds are naturally-occurring carbon crystals. They are produced by pressure and heat miles under the ground.

But these days, it is just a matter of making carbon crystals in a lab. These are synthetic diamonds, created by heating and compressing graphite. This approach differs from the geological methods used to create real diamonds.

Synthetic Diamonds and Their Variety

Synthetic diamonds, often known as lab-developed diamonds, are gaining popularity. This is because they are inexpensive and widely available. While they may not have the same history or sentimental value as a natural diamond, lab-grown diamonds are chemically identical to their natural counterparts and offer the same beauty and durability. 

They also provide buyers with various options, such as different diamond styles, colors, and cuts.

As a result, people with modest budgets who still want the look of real diamonds now often buy lab grown diamonds. After all, they work magic in any event, from wedding rings and tennis bracelets to diamond earring studs. In addition, lab-grown diamonds are less likely to be associated with conflict or human rights abuses, making them a more ethical choice for some consumers. 

What’s more, unlike natural diamonds that form over billions of years, synthetic diamonds are made in just a few weeks.

Whether you’re looking for a new engagement ring or just a pair of sparkling earrings, lab-grown diamonds are a great option to consider.

Unfortunately, the term “synthetic” is frequently used to deceive consumers into believing that these are not real diamonds. This isn’t the case. In fact, these synthetic diamonds consist of the same material as genuine diamonds.

How Labs Produce Synthetic Diamonds

The conditions that produce natural diamonds are mirrored in lab-generated diamonds. Diamond synthesis involves a variety of techniques. Only two approaches, however, are commonly employed. They are;

1. High-Pressure High Temperature(HPHT)

Previously, we got diamonds created in the lab by mimicking natural conditions. HPHT is a commercial technique used by a variety of businesses. It generates diamonds in different colors. The method generates pressures of over 55000 bars and temperatures of around 1500C (2732 F) using an upper and lower jaw. It starts by encapsulating a starting material, usually graphite.

This method produces diamonds in a relatively short time. There are different presses in HPHT. Each procedure aims to generate a high-pressure, high-temperature environment conducive to gem formation. They also begin with a microscopic diamond seed set in carbon and grown under extreme pressure and heat.

They include:

  • Belt Press

Diamond synthesis using a high-pressure, high-temperature (HPHT) belt press. It uses an upper and lower jaw. The pure carbon melts in this process and begins to form diamonds. The belt press was the first press used in lab-created diamonds. It is still in use today, despite significant technological developments and changes.

  • Cubic Press

A cubic press works similarly to a belt press but with six anchor bolts to work with bigger, cubic elements. Although a cubic press can exert more pressure than a belt press, professionals cannot scale it in the same way. As a reason, cubic presses are less regularly used than belt presses.

  • Split-Share (Bars) Press

\The split-sphere press has eight outside anvils and six smaller inner anvils to increase capsule pressure. The capsule is inserted inside an oil-filled cylinder to speed up heat transmission. This allows for a considerably faster reach of greater temperature.

HPHT Technology and Colors

HPHT Technology and Colors

Different HPHT-processed diamonds come out in various colors. They are:

  • Yellow and Green Colors

If a diamond includes nitrogen in the form of A, B, or both, it can dissociate under particular HPHT circumstances, resulting in single substitution nitrogen. B can even dissociate in commercial operations. The dissociations yield different colors in diamonds.

This method is used to make green, orange, and yellow diamonds, but it is also utilized as the initial stage in producing pink diamonds that are later radiated.

This procedure uses smaller diamonds ranging from 0.20 to 1 carat. The initial materials are all hues of brown, with yellow color acting as the modifier.

  • Colorless Gems

If a diamond includes a trace amount of nitrogen, we classify it as I-Ia, and if it contains nitrogen in form B, we classify it as Ia-B. Under HPHT settings, these diamonds experience plastic deformations.

This realignment improves the crystal bar and brings it closer to stability. As a result of this process, the brown color is removed, and colorless diamonds are obtained. Light pink is also obtained as a result of a partially enhanced crystal bar.

This category of diamonds is extremely uncommon, accounting for only 2% of all diamonds of all sizes.

  • Blue Color

When a diamond has just a trace amount of nitrogen and an element of boron, it is classified as the I-Ib type. This category of diamonds is the rarest, accounting for only  0.1% of all known diamonds.

The method is the same as for I-Ia and Ia-B diamonds, and the color ranges from pale blue to greyish-blue depending on the boron ratio and the extent of deflection. As indicated for I-Ia and Ia-B diamonds, the initial hue is a shade of brown, with a very little blue.

2. Chemical Vapor Deposition (CVD) Technique

Chemical Vapor Deposition (CVD) technology is a more modern alternative to HPHT. It was invented to create a  reproducible diamond first in the late 80s. It uses gas as a carbon source, usually methane (CH4) and hydrogen. After that, carbon may be placed onto a suitable substrate.

Hydrogen ions erode any graphite that grows on the substrate far more quickly. Diamond is the sole form of carbon left at the end of the synthesis due to the speed of the surface reaction. CVD crystal gem sizes range from less than 0.25 to roughly 0.74 carats.

CVD diamonds belong to one of these categories;

  • Nanocrystal CVD diamond
  • Polycrystalline CVD diamond
  • Single-crystal CVD diamond

Nanocrystal diamonds are crystals or films with individual diamond crystals smaller than 500 nanometres. Interconnecting diamond crystals generally greater than one micron are polycrystalline CVD diamonds. Nanocrystals don’t have all of the diamond’s distinctive features.

The CVD method can manufacture large-area discs of a thick polycrystalline diamond with a diameter of 15 cm.

A single-crystal diamond is generated via product development (growth extending outwardly from a crystal’s surface in all directions). A single-crystal diamond serves as the substrate. The CVD technique is quite slow and takes about a month to create a 1-carat diamond.

3. Other Techniques Used

Other technologies employed in making synthetic diamonds are detonation and ultrasound methods. They are helpful in the production of Nanodiamonds.

Conclusion

When getting a lab-grown diamond, you might be unsure of which one. Luckily, you do not have to go through all that stress. This is because lab-created diamonds are all the same irrespective of the type of technology. They also pass the 4Cs of diamond testing used for mined diamonds.

In light of this, the quest for a bigger gem for a smaller amount continues. The pace of innovations in synthetic diamond technologies will continue to increase.

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