Amorphous Lab Created Diamonds - The Ultimate Guide

The amorphous diamond.  The name in and of itself is a bit of a conundrum.

After all, we have the word amorphous, which means to have no shape, and then we have the word diamond, which is something that always has a shape.

How is it possible to have a diamond with no shape, and furthermore, why would anyone want one?

Amorphic diamonds may sound like a bit of an oxymoron, but amorphous diamonds do indeed have a shape, and, in most cases, a very well-defined one. The “amorphic” part of the name refers to the carbon inside of the diamond and it’s lack of a long repetitive structure that is characteristic of most crystals, not the diamond itself.

Still a bit confused? We’ll clear it all up for you.

This article will cover the following:

  • What is an Amorphous Diamond?
  • Who Created the First Amorphous Diamond?
  • How are Amorphous Diamonds Made?
  • What’s the Durability of Amorphous Diamonds?
  • What’s the Clarity of Amorphous Diamonds?
  • What Color are Amorphous Diamonds?
  • The Sparkle and Fire of Amorphous Diamonds
  • Amorphous Diamonds vs. Real Diamonds: The Verdict

What is an Amorphous Diamond?

As mentioned in the intro, an amorphous diamond is one that lacks the repetitive structure of crystals. That may explain what they are, but that really doesn’t explain why we would want one.

One of the most negative aspects of working with a natural diamond is the fact that, even though the diamond is one of the strongest minerals in the world, it still has planes of weakness. These are the places where jewelers usually cut the diamonds to cleave the facets that give the diamonds their sparkle, which is a good thing.

We want sparkly diamonds, it’s one of the main selling points.

However, sometimes we want diamonds for other things, and we want those diamonds to be extremely durable, and that's where amorphous diamonds really shine. When a diamond is amorphous, it has strength in all directions, and that uniform durability can make diamonds useful for a lot of other applications, like cutting tools and water-resistant parts used for transportation. 

Some people still like to use Amorphous diamonds for jewelry as well, but in most cases a lab created diamond is all of the durability you’ll need.

That said, there are new methods being investigated for more widespread use of the amorphous diamond. These involve the use of machinery which exposes the diamonds to extremely high pressure, preparing them for use in applications which involve more endurance such as those that would be needed for industrial cutting tools. 

Who Created the First Amorphous Diamond?

The term "diamond-like carbon" or DLC, was first introduced in 1971.  In the 1950's, a high-pressure method for diamond synthesis was developed, but it required costly special equipment making it highly impractical for most people and companies. The search for a cheaper method began, and in the following years, an extensive amount of research was done on vapor phase synthesis using hydrocarbon gases or carbon vapor to grow diamond crystals.  I sounds complicated, but this was found to be the solution to creating more cost effective DLC materials.

Aisenburg and Chabon were the first to yell, "Eureka" in 1971, by publishing a paper on the successful creation of an amorphous hard film made mostly of carbon. The method used an ion beam to sputter carbon electrodes in an argon atmosphere contained in the plasma, later called DLC.  In other words, they found a way to utilize a machine to alter chemical components to officially create diamond like carbon. 

From there, the race to find a more efficient method was on.

Following the publishing of the Aisenburg and Chabon papers, various DLC methods were developed creating superior characteristics with the materials such as low friction, high hardness, lubricated material and better chemical stability driving the need for DLC’s forward. The low amount of friction in DLCs is appealing because it addresses environmental concerns. The use of DLC in automobiles reduces fuel consumption and is currently being used in driving and pump components to prevent engine seizure. Currently, there are two popular methods for producing DLC's, including Physical Vapor Deposition (PVD) and Chemical Vapor Deposition (CVD).  While we won’t get into the scientific explanation of those methods here, just know they are what people typically use to create DLC’s. 

The main difference between the PVD and CVD methods is that PVD uses a solid, such as graphite for its deposition process, whereas CVD uses a gas, such as a hydrocarbon or methane.  This subtle change adjusts the final DLC produced and slightly modifies the final product. 

How are Amorphous Diamonds Made?

Using the chemical vapor deposition (CVD) process to make an amorphous diamond involves a gas phase chemical reaction which occurs above a solid surface.

The first step in the CVD method is activating the carbon-containing gas molecules necessary for this reaction to take place. There are various ways of doing so.

The molecules can be activated by using RF- plasma, DC plasma, microwave plasma, or electron cyclotron resonance microwave plasma.  Although the methods differ in detail, they all share a few basic components.

All require that the precursor gas must be diluted to an excess of the hydrogen gas, and the temperature of the substrate must be heated to at least 700 degrees, in order to ensure a diamond will form.

Again, this is all very scientific in nature but it basically comes down to the fact that someone has to heat up gas molecules to create a reaction.  From that point, the gas gets diluted and in time, it will form a diamond. 

Radiofrequency discharge plasma method

In the 1970's, studies were conducted on the possibility of using a CVD method which involved exposing a base material gas, to a glow discharge plasma made of hydrocarbon gas.  In these studies, RF (radio frequency) was used as a main method of discharge. Using acetylene or methane as the base material gas, a DLC film was formed by emitting ions or radicals into a hydrocarbon gas plasma at a relatively low temperature. 

PIG Plasma Method

Another CVD method used to create an amorphous diamond, the  Pig/Plasma CVD method exposes hydrocarbon gas to plasma to produce a DLC. This process allows easy control of hardness, thickness, and stress of DLC film, which means it can be used for a wide range of applications. Also, since plasma occurs in a range of conditions, the power and raw material gases can be used efficiently. Although the resulting DLC is not as hard as that in the arc PVD method, it can form films with a wider variety of uses than the RF CVD method.

Sputtering/Plasma CVD-composite method

The sputter/ plasma method applies a high-frequency power to a sputter vapor source made of graphite. In this method, positive ions in inert gas plasma collide with graphite to spew out carbon atoms. The DLC film is formed by letting the hydrocarbon gas into the furnace. The use of hydrocarbon gas can significantly increase the rate of deposition.

Arc - PVD method

In the arc-PVD method, a DLC is formed on a base material by creating a vacuum arc discharge on a graphite surface to generate carbon atoms. This method allows the simple formation of hard DLC diamonds with more diamond and less graphite than CVD DLCs. Also, the small size of the vapor source means that the film can be formed at a higher speed by using many vapor sources at the same time. However, there is a likelihood of contamination by coarse particles left unionized during the arc discharge, resulting in roughness on the surface of the DLC.

Filtered arc- PVD method

The filtered arc-PVD method was developed to weed out the coarse particles using a magnetic filter. While the arc- PVD method was successful in preventing the coarse particles from reaching the base material, it also slowed down the rate of deposition causing a lowering in productivity.

Durability of Amorphous Diamonds

While part of the intention of creating an amorphous diamond is durability, it’s also to make a diamond that is stable. Although the amorphous diamond rates a more than respectable 9.8. On the Moh's hardness scale, it still has not taken the crown from the diamond. This makes the amorphous diamond the hardest mineral next to the diamond, but it’s still not as hard as the natural version.

The main benefit of using the amorphous diamond is not that it’s harder than the natural diamond, but rather more stable. After extreme heat and pressure are placed on the carbon it’s still able to retain its structure and imcompressibility, whereas the natural diamond does not. The result is a forming a dense, durable, strong, and thermally stable product with a wide range of applications that the diamond cannot be used for. Thus, the amorphous diamond is extremely durable, but not harder than the natural diamond.

The Clarity of Amorphous Diamonds

Although, strictly speaking, an amorphous diamond is not a real diamond, it is subject to the same scale of clarity that a real diamond is. The clarity of a diamond is determined by the amount of carbon spotting or other internal flaws in a diamond. If you look through a jeweler’s microscope and no flaws are spotted, the diamond is characterized as “FL” or flawless, the highest grade of diamond clarity, whereas a diamond with obvious flaws might receive an I-2 or I-3 assignation, the lowest on the clarity scale.

In terms of clarity, a real diamond and lab created amorphic diamond are on the exact same scale, and there is very little difference between the two in this area.

In fact, when it comes to clarity of amorphous diamonds vs. real diamonds, the clearest difference is cost. An almost flawless diamond can send you into debt, whereas you can purchase an amorphous version at the same weight and clarity for a cool $150.

While the filtered arc PVD method can be used to prevent flaws and produce an amorphous diamond with greater clarity,  it also slows down the rate of deposition, leading to lower efficiency of diamond production.

Color of Amorphous Diamonds

In addition to clarity, the color of amorphous diamonds is also graded using the same scale as the one used for natural diamonds. The GIA Diamond color chart scale ranges from the most desirable D-F category, used to identify white diamonds, to the S-Z category, which is used to describe diamonds with a light color. However, customers generally shy away from the S-Zs because of their yellow tint, and most naturally mined diamonds fall far from D side of the scale, leaving the jeweler preferred of diamond color in the F-I range. This is the range in which amorphous diamonds fall. 

To the untrained eye, an F diamond appears almost identical to the D rated diamond.  F diamonds are almost completely clear and the flaws are nearly undetectable. I diamonds are near colorless, and in the right setting can betray any hint of color, making the F-I range ideal for customers and jewelers. Since the molecules in the amorphous diamond and natural diamond are small, the light is not impeded, letting the pure whiteness of the diamond show through. This shared property makes the difference in color between the amorphous diamond and mined diamond nearly imperceptible.

Sparkle and Fire of Amorphous Diamonds

There's nothing like the fire of a diamond to put the fire in a diamond, and when it comes to fire, the amorphous diamond is burning on all cylinders. Whether it be real or synthetic, a diamond has prism-like qualities which divides light into a rainbow-like spectrum that reflects light causing the diamond to emit flashes of color. These colors give the diamond its fire. The more color it reflects, the color grade of the diamond. That's where the amorphous diamond earns its real points.

Since the amorphous diamond is balanced to look like a flawless diamond, it has a high white light return, giving it the luster and brilliance of a white diamond.

While natural diamonds can also be faceted to produce a brilliant fire, the diamond cutters are more focused on maximizing the weight of the diamond as opposed to the aesthetic quality of the end result. Makers of amorphous diamonds are not concerned with the weight of the diamond and can focus on its spectacular fire.

Amorphous Diamonds vs Real Diamonds: The Verdict

Sometimes it has to be real, but sometimes, it’s so realistic that it’s worth the sacrifice. Is this the case with the amorphous diamond?

When it comes to the fight between amorphous diamonds vs. real diamonds, there are two applications: the practical and the impractical. 

In terms of practical uses, it seems obvious that the amorphous diamond is the hands-down winner. The amorphous diamond has already been found to be useful in decreasing fuel intake, is being introduced to car components to prevent seizure, and its industrial uses have yet to be fully explored.  Certainly, a real diamond would not be able to compete in this arena because it’s simply too expensive and rare to use in commercial applications.

However, even from a less practical standpoint, the amorphous diamond seems to have quite a few perks as well. Unless you have a six-figure income, a flawless D diamond is a little beyond reach, and while you may never find a flawless amorphous diamond, you won't be able to spot the flaws. It's also quite close in hardness to a diamond. When it comes to clarity and color and durability, so the amorphous diamond and the real one is almost identical.

Now we come to the fire, or the sparkle of the diamond. We don't call a diamond a sparkler for nothing. If you really want something eye-catching, no real diamond out blazes the amorphous diamond, and when it comes to price we have a clear winner.

At a mere fraction of the cost of real diamonds, the amorphous diamond is the better deal hands down if you’re willing to get beyond the fact that it’s not a naturally occurring diamond.

So, what do you think? More fire on the hand, more money in the bank - sounds like an obvious choice. We’ve given up chicken for soy, cow’s milk for almond milk, and even pizza crust for cauliflower.

Is the real choice always the best choice?

Either way, there is no doubt we’ll be hearing and seeing a lot more about amorphous diamonds in the future. With advancements in the manufacturing procedure in the works, we may not have even begun to tap the surface on the potential of these beauties. 

And, if they’re that popular in the world of science, just imagine how popular they’ll be in the world of fashion and beauty

So, would you wear an amorphous diamond? What do you think the future has in store for amorphous diamonds, and, more importantly, what do amorphous diamonds have in store for our future?

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1 comment
Pamela A Scallan says May 4, 2019

Where do I buy amorphous diamond engagement rings

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