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Are Diamonds Bulletproof? Can A Bullet Break A Diamond?

Are Diamonds Bulletproof? Can A Bullet Break A Diamond?

When we look at the hardness of a diamond and how much these minerals get praised for their level of endurance, it’s easy to think diamonds are harder than they really are.

One of these common misconceptions is that diamonds can withstand a direct impact from a bullet and stay in one piece. That’s why today we’re addressing an oh-so-important question: Are diamonds bulletproof, or can a bullet break a diamond? Let’s start with the straightforward answer:

Diamonds aren’t bulletproof. A bullet can – and will – break a diamond with ease. What circumstances need to be present for a bullet to break a diamond is a bit more complicated to explain.

So, let’s dive in and see why diamonds aren’t bulletproof, why can’t a diamond stop a bullet – and maybe find out what materials are capable of doing so.

Why Can’t A Diamond Stop A Bullet?

Just because diamonds are rated as one of the hardest materials on Earth, that doesn’t mean that they’re capable of stopping a bullet. But before we even get to that, what does “bulletproof” even mean? 

In short, it’s a term that’s used to describe a material or a surface that’s capable of resisting – or absorbing – the impact of bullets without sustaining damage. 

Now, bullets are made of lead – a fairly soft metal. But the reason they are capable of breaking a diamond, despite the fact that diamonds are harder than lead, is that bullets pack an immense force. And on impact, that force doesn’t just disappear – it dissipates, or it gets stored. 

Diamonds are exceptionally hard, but they’re not tough by any means. What this means is that diamonds aren’t flexible or capable of adapting to the force that is coming towards them. Since that is the case, they aren’t really good at absorbing the energy without any damage.

When they come into contact with the amount of force that a bullet brings with it, they can break.

What’s the difference between hardness and toughness, you ask? The hardness of any given material, including diamonds, can be defined as the ability to withstand abrasion and the overall surface durability. On the other hand, toughness typically refers to the material’s material’s ability to resist breaking. 

And no, materials that are hard aren’t also tough by default. 

That brings us back to diamonds. It’s super-hard to scratch or otherwise damage their surface, but hit them with enough sudden force, and they could turn into a fine dust.

Diamonds Vs. Common Ammunition Types

It’s pretty hard to talk about bullet damage and not specify which bullets we’re talking about here. We’ve been thinking long and hard about what we can do to make it a bit easier for you to understand – and for us to explain.

We’ve concluded that we will be talking about two of the most common bullets: The most common pistol round and the most common rifle round that’s used.

Before we get to that, here’s a brief overview of how the force of a bullet is typically measured, using the 9x19mm pistol round as an example.

The force of a bullet is measured in foot-pounds or joules. The first method is much easier, so we’ll use that one for the sake of simplicity.

A 9mm bullet carries around 350 foot-pounds of force with it. That means that that bullet striking 350 pounds of something that will stop that bullet immediately will send that object 12’’ into the opposite direction.

Now, that must seem like a lot of force, but it’s not that much in actuality. Pistol rounds pack a lot less power than the majority of rifle rounds.

Diamonds will break with a lot less than 350 foot-pounds, so a much smaller caliber – such as .22 LR – can also shatter a diamond in almost every situation.

The amount they repel is much more than other materials. However, it’s not quite enough to be undamaged by a pistol round as small as a 9mm one.

That means that the second the round hits the diamond and the energy transfers to its surface, the force with which the bullet hits will be enough to shatter the diamond into pieces.

There’s no way around it. The force is too great, and diamonds are too hard to absorb any kind of significant kinetic force from the bullet. 

Now let’s talk about the rifle rounds. The most common rifle round used all around the world is 7.62×39. That is the round that’s used in the famous AK-47 rifles.

This round is known for both its penetrative and stopping force. That means that the bullet is several times larger and stronger than the earlier mentioned 9mm pistol round.

It’s quite obvious what will happen if you fire this round into a diamond. A bigger bullet causes more extensive damage – and brings quite a bit more force with it, too.

If this experiment takes place, you’ll have a hard time even finding the bits and pieces of the destroyed diamond. The kinetic energy surrounding this round is so extreme that it will probably turn this precious stone into – well, precious dust.

We won’t even bother getting into larger bullets, like 7.62x54R sniper ammo. What’s the point of talking about them when it’s evident that they’re more than capable of turning virtually anything into dust, right?

How Much Force Can A Diamond Withstand?

Instead of talking about what will shatter a diamond into pieces, let’s turn this conversation on a more positive note and look at some things that a diamond can withstand. 

First of all, how much force does it take to shatter a diamond? 

Well, people say that sometimes two pounds of force can break a diamond. Three pounds is a force with which you have to hit a diamond in order to shatter it almost every time, and a hit of four pounds or more is more than enough to break a diamond.

So, in any situation where you’re putting less than, we’d say, three pounds, a diamond will stay intact.

The good thing is that you can’t generate this force by throwing or dropping a diamond by hand. If you drop it by accident or throw it into a wall or a solid surface, there’s more than a good chance that the diamond will survive without a scratch.

On that note, it’s generally a good idea to keep your diamonds away from any kinds of hydraulic presses since these things can generate much more force without any effort.

See, it seems that there’s a recurring theme of things that can easily destroy a diamond, but don’t get the wrong impression: Diamonds are the hardest in the sense of their density and durability to withstand many other conditions that would cause a substantial amount of damage to other materials.

That’s why diamonds are among the strongest materials in the world, not because they can stop a bullet with ease.

The main property of a diamond that makes it so durable, as we’ve explained earlier, is the fact that any real diamond is virtually unscratchable. 

If you try to put even a tiny indentation on the diamond’s surface, the chances are you’ll fail. That’s because of the density of the diamond and the hardness that comes with it.

If Not Diamonds, What Things Are Bulletproof?

First of all, the most common bulletproof thing is Kevlar. And by “most common,” we mean – it’s the thing that most bulletproof vests are made of these days. 

There have been a few tries at making diamond bulletproof vests, but without any success. We are pretty sure that by now, you can see why. 

Kevlar is essentially a kind of plastic, which doesn’t make much sense. 

“How can a plastic material stop a bullet and a diamond can’t?” you might ask yourself. Well, it’s because of the properties of said plastic that diamonds don’t have.

For starters, structural flexibility and resilience. Kevlar is usually bent in and dented after being hit with a bullet, meaning it’s capable of absorbing a good portion of the bullet’s kinetic energy.

How does Kevlar have those characteristics? 

Well, it comes from the way Kevlar is made. Kevlar is a manufactured plastic, and it’s made of a chemical compound called poly-para-phenylene terephthalamide, in a chemical reaction between a chemical solution containing nitrogen and hydrogen and an acid.

On the other hand, diamonds are anything but artificial. 

The process of forming diamonds is natural and takes place underground. We can’t influence it in any way or make diamonds have specific characteristics that they aren’t supposed to have, such as resilience. 

Diamonds are hard; they’re a 10 on the Mohs scale. However, they’re not that strong and can even be labeled as “brittle” and unable to absorb the bullet’s energy with ease.

That’s the exact problem that makes diamonds not bulletproof. The process in which a diamond forms from carbon makes the atoms of carbon crystalize and harden. Particles that underwent that kind of change won’t be able to exhibit any sort of flexibility. 

Another thing that isn’t that flexible – but is definitely bulletproof – is steel

Earlier in our history, bulletproof vests were made from steel. Or, to be more precise, the vests were made so that you can fit steel plates meant to stop bullets from penetrating inside them.

Learn More: Is Steel Harder Than A Diamond?

That might be confusing since steel isn’t that flexible. As a matter of fact, steel isn’t flexible at all in its cooled state. However, steel has an ionic structure that allows it to absorb kinetic energy – even when it’s coming from a bullet.

These two materials – Kevlar and steel – are the most common bulletproof materials used these days.

Their flexibility and ability to absorb kinetic energy make them perfect for the job. Diamonds, as hard as they are, don’t have either of those qualities – and that’s why they shatter when hit by extreme, sudden forces. 

Even if you were to make a wall of diamonds and fire a pistol round into it, the results would virtually be the same. The brittleness of the diamonds doesn’t change by enlarging the surface.

It might reduce the damage done to that “diamond plate,” but it certainly wouldn’t stop a bullet – not even a smaller pistol round, let alone a big rifle bullet.

Final Words On The Topic

It seems pretty evident that the final verdict on “are diamonds bulletproof” and “can a bullet break a diamond” isn’t looking that good for the diamonds. To be crystal clear, pun intended: 

Diamonds aren’t bulletproof, and a bullet can, in fact, break a diamond. That doesn’t mean that you should think less of the diamond’s fantastic ability to withstand a substantial amount of damage. Remember, diamonds were never intended to stop a force such as the kinetic energy of a bullet.

Since this is the case, we would highly advise you to keep your diamonds away from anything that could shatter them in pieces. That includes hammers, hydraulic presses – and, yes, even bullets. All of these are a diamond’s equivalent of Kryptonite and will damage it beyond repair.

And while we’re at it, if you had a brilliant idea to make a diamond bulletproof vest, you should consider the alternatives, like Kevlar. And most importantly, remember that it’s not a good idea to experiment with firearms unless you’re a trained professional.

We hope your diamonds stay in one piece and that you don’t get any funny ideas about super expensive shooting target practice!