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Do Diamonds Break Under Pressure?

Do Diamonds Break Under Pressure?

While diamonds are famous for their exceptional beauty, they’re also the hardest material on Earth. However, we should say that you can potentially break your diamond yourself. Now, you may be wondering: Do diamonds break under pressure?

If the pressure you apply to the diamond is high enough, it’s going to break. However, you would need a hydraulic press to achieve that. Then again, you can also utilize high pressure to change the color of the diamond – but how is that possible?

In this article, we’ve covered everything about the link between diamonds and high pressure. 

Before we get to that, we need you to understand how pressure impacted the diamond’s formation. So, without further ado, let’s dive in.

How Are Diamonds Formed?

Diamonds were made deep in the Earth, in a layer that separates our hospitable exterior from the molten core, also known as the mantle. Temperatures boiled above 2000 degrees Celsius, and pressure exceeded 70,000 atmospheres. 

These extreme conditions modified graphite on the atomic level. This restructured molecular composition of graphite was triangular instead of hexagonal, thus creating a diamond. 

Luckily, nature also has a method of transporting diamonds from deep within the Earth to the surface – volcanic pipes. 

Deep source volcanos start much deeper than your typical volcano does. The high amounts of magnesium and carbon dioxide build-up force the lava up to the Earth’s surface, resulting in a violent eruption.

Diamonds are usually elevated through Kimberlite pipes. When mining these sites, precious and semi-precious stones such as peridot and garnet can also be found – along with diamonds.

Learn More: Diamond History: How They Form And How They’re Found

Other Sources Of Diamonds

Diamonds aren’t only formed under the extreme pressure and heat within the Earth. They can also develop during a collision between our planet and an asteroid. 

Russia claims to have a deposit of diamonds that resulted from a collision over 35 million years ago. These diamonds that were created during a cosmic collision aren’t likely to be of gemstone quality. 

However, these stones maintain their strength and are commonly used for cutting and any other industrial purposes. 

Just as glass results when lightning strikes sand, diamonds made from asteroid impact are far from meeting the typical engagement ring’s standards of color, cut, and clarity.

In addition, meteorites are also known to deliver diamonds. 

Carbon is one of the most abundant elements in the universe. So, it shouldn’t come as that big of a surprise that diamonds aren’t exclusive to just our planet, the Earth.

When scientists tracked meteorite impact, they weren’t surprised to discover diamonds but were astonished by the size of these diamonds. Scientists concluded that diamonds of this size could only form within a planet, meaning these diamonds could’ve come from some planet destroyed millions of years ago.

Synthetic Diamonds

After learning about nature’s process of making diamonds, the creation of synthetic diamonds might have less “sparkle.” The first artificial, lab-made diamond was created in the General Electric lab back in 1954.

This lab-grown diamond was created through the unique process called High-Pressure High Temperature – or HPPT for short – which tries to imitate natural conditions by superheating and applying extreme pressure to diamond seeds.

Synthetic diamonds are more commonly created by using Chemical Vapor Deposition, which can take 28 days. The process starts with diamond seeds that are heated in plasma, and as a result, we get cube-shaped diamonds.

What Is High-Pressure High-Temperature Treatment?

The HPHT treatment was invented in the 1950s to make the diamond industry more lucrative. The process is actually having a negative impact on today’s diamonds industry: HPHT diamonds are cheaper than natural diamonds and develop significantly better colors after the process.

Companies buy cheaper, less desirable stones, put them through the HPHT process, and sell the resulting diamonds at much higher prices. This process allows producers to select flawed diamonds and alter them into more desirable stones of various colors.

The HPHT Process

HPHT is a method applied to those diamonds that aren’t fully crystallized when released from erupting volcanos. 

The HPHT process is utilized to finish what nature started by applying 70,000 atmospheres at temperatures up to 2000 degrees Celcius – the same conditions that a diamond gets within the Earth.

Meeting these conditions will bring a stone to its fully mature state. 

The HPHT process requires careful positioning of the stone by a highly trained gemologist. The diamond is positioned into a containment cube that’s surrounded by the heating system. 

The cube is then transferred in a press to apply the immense pressure, the same one that the Earth “provides” when creating diamonds. This process brings the stone to its most desirable state.  

These mature lab-grown diamonds are defined as those that have D thorough H color grades.

In essence, the HPHT process finishes what nature started. However, this process can also be used to alter the color of diamonds artificially.

You can only apply the HPHT color treatment process to stones of the highest clarity. The gems must also be flawless because, during the process, diamonds with inclusions or blemishes can break. 

Even the slightest inclusion can result in blowing up the diamond during the process, therefore rendering it useless.

The only permanent color enhancement process is the HPHT – it’s the only treatment that can thoroughly saturate a diamond with color. And unlike irradiated and coated diamonds, HPHT diamonds are impervious to change and require no special care to maintain their color.

On the other hand, irradiated diamonds are prone to color fading at high enough temperatures, and both irradiated and coated stones can’t be polished or recut without impacting their color.

Advantages Of Buying HPHT Diamonds

The biggest benefit of buying an HPHT diamond is having the ability to buy the highest clarities in diamonds with average savings from 50-70%. 

For instance, a round cut 1.5 carats D VVS1 natural diamond can cost around $32,700 online, whereas the same gem treated by HPHT color treatment sells for $11,400.

Colored diamonds, while being rather popular and desirable, are rare and thus more expensive, making HPHT diamonds an affordable alternative.

Another advantage is that synthetic diamonds generally place less strain on the environment as they don’t require mining in mineral deposits.

Concerns When It Comes To HPHT Diamonds

With many consumers wanting to buy the biggest and the best gemstone, the demand for HPHT diamonds continues to grow. 

These enhanced diamonds allow consumers to get a bigger gemstone with a better color grade for less money than they would typically pay for a natural diamond of similar specifications.

Buying HPHT diamonds isn’t recommended for few reasons. 

These enhanced gemstones can show hints of color visible from the side of it upon close inspection. They’re also prone to losing some of their original weight and clarity during the HPHT process. 

What’s also concerning is that HPHT diamonds tend to have magnetic properties, and some can even be picked up by magnets.

Responses From The GIA

It’s rather difficult to distinguish natural diamonds from HPHT diamonds, so some buyers accidentally purchase enhanced diamonds thinking they’re real. 

The GIA wanted to rectify this situation to help prospective consumers truly understand whether they looked at a natural or enhanced diamond.

So, a team led by the research director of the GIA put gems through various tests to indicate whether they’re natural or not. Scientists discovered that advanced spectroscopic methods needed to be utilized to understand the difference between natural and HPHT diamonds.

A diamond viewer is used to detect lab-grown diamonds by looking for unique spectroscopic features such as a lack of natural graining in the diamond.

Now that you know that high pressure can be utilized in the diamond industry, let’s talk about the chances of breaking your diamond.

Related Read: What Is The Difference Between HPHT And CVD?

Can You Break A Diamond?

Technically speaking, a diamond can be broken. However, in actual practice, it’s rather difficult to break a diamond. You would have to hit it in the exact right spot and be sure that you’re using enough force.

To say something is hard doesn’t mean that the same thing is strong. 

Let us elaborate: You can scratch steel with a diamond, and on the other hand, you can easily shatter a diamond into pieces with a steel hammer. The diamond is hard; the steel hammer is strong.

Whether something is strong or hard depends on its internal structure. 

As you already know, a diamond is made purely out of carbon atoms connected in a lattice-type structure. Each carbon atom is a set distance from the next. Moving two atoms closer or further away requires an extreme and sudden force.

That is exactly what makes a diamond so hard – and why it’s able to scratch any other material.

Adversely, steel has an ionic structure. Simply put, it’s similar to that of a handful of raisins in a jar of honey. You can move any of the atoms easily, and any force is easily absorbed. If you hit steel with just about anything, it’ll absorb the blow by shifting the atoms instead of shattering.

That is what makes steel incredibly strong and easy to work with, while diamonds, due to their lack of flexibility in their structure, aren’t strong at all.

How Diamond Cutters Break Diamonds?

Have you ever wondered how any diamond ever gets to its final state if nothing else can even scratch it?

The first step in processing a rough diamond is to separate it into the highest available number of stones, and this is done by using the diamond’s cleave lines. These lines are weak spots of diamonds. 

With a sharp blow of a metal cleaving tool, the rough stone will split along cleave lines. 

But the drawback is that a rough diamond has four cleave lines. Each of these can impact how many single polished diamonds the rough stone can produce.

In some cases, an inspection of a rough stone can take weeks or even months before selecting a particular cleave line. That is especially true for diamonds of higher quality.

Can You Break A Diamond With A Hammer

Technically speaking, you could break a diamond with a hammer. However, it would be pretty hard to achieve it. 

In most cases, you could smash a hammer over a diamond, and it will do absolutely nothing to it.

Here’s the thing: To break this gem with a hammer, find a diamond that has inclusions or blemishes. Aim for the hammer blow to deal maximum force against the weakest internal spot of the stone. And lastly, do not let the diamond jump when you hit it.

As you can see, even though it’s technically possible to break the diamond with a hammer, it’s usually a pretty challenging task.

How Do Polished Diamonds Break?

Weaknesses such as inclusions and blemishes are still present in polished diamonds. So, due to the structure of a polished diamond, there’s always a risk of chipping the stone. 

It doesn’t even need to be a particularly hard impact – nor a tough surface.

Just clipping the stone at the exact right angle could split it in two. It’s not rare for engagement rings to suddenly be missing a piece of girdle or crown of the diamond. 

Certain types of cuts can expose some parts of the diamonds more than others.

Final Words

If you’re still confused about the question, ”Do diamonds break under pressure?” let us break it down for you:

In order to break a diamond using high pressure, you would need to utilize a special hydraulic press, which can apply immense pressure on the diamond. You could potentially do it yourself, but that would be an arduous task.

On the other hand, high pressure can be utilized along with high temperature to treat diamonds and alter their color artificially. So, while high pressure is a diamond’s enemy, it’s also an ally in terms of treating the gem and making it more marketable.

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