While diamonds are the highest rank of hardness (ranking 10 of 10 on Mohs Scale of Mineral Hardness) they only rank fair-to-good when evaluating mineral toughness. So, while diamonds are essentially unable to be scratched by anything other than another diamond, diamonds can, somewhat easily, be smashed by a hammer.
Diamond, commonly known as the hardest material in the world, is not only beautiful but it is also incredibly resistant to scratching. However, hardness shouldn't be confused with toughness. Diamonds can be crushed with any hard enough object that is brought down with enough force.
Diamonds do not shatter when dropped, but they may chip from powerful, accidental blows. They can also break when there is pressure buildup inside the stone called 'strain. ' A small tap results in breakage for the pressure to escape. While it is very rare for diamonds to break this way, it's a fact worth noting.
Modulus of rupture of diamond is around 3000 MPa. Around 6.000 tonnes or the weight of 100 trucks. That assumes perfect compression, so there is a mechanism to distribute the load perfectly on the sphere.
It's important to remember that diamonds are the hardest stone on the Mohs Hardness Scale, making it nearly impossible to scratch them unless done so by another diamond. If you're willing to risk it, take a knife and gently scratch the surface of your stone. If it scratches immediately, the stone is synthetic.
Toughness: Diamond's ability to resist breakage and chipping allows it to become impervious to damage. However, the stone can break or fracture when hit with heavy metal or rock, weakening crystal bonds within the stone.
As an example, you can scratch steel with a diamond, but you can easily shatter a diamond with a hammer. The diamond is hard, the hammer is strong.
Indentation strength tests have shown that wurtzite boron nitride (w-BN) is stronger than diamond, and that lonsdaleite, which is also known as hexagonal diamond due to its carbon composition and similarities to diamond, is 58% stronger than diamond.
Chips typically occur when the girdle (edge) or point of a diamond strikes something hard. Bathroom and kitchen countertops, as well as jewelry items with diamonds worn next to each other, are common causes of chips.
Diamonds are exceptionally delicate, and thus, they require the utmost care. Harsh chemicals like acetone, chlorine, bleach and other abrasive substances like baking powder and toothpaste will damage your diamond beyond repair.
A small, fast bullet will likely not break a diamond. But a large, slow bullet will. So many occurrences can damage or completely destroy this precious stone, that it's hard to list them all.
So, yes, diamonds can break. This comes with good news and bad news. The bad news is that no diamond is impervious to breaking, but the good news is that it is an extremely rare occurrence.
Diamonds can break during normal wear. You may not see anything when the diamond falls, but they can form cracks over time. If your daily job involves doing heavy tasks like lifting weights, farming or nursing, you should avoid wearing your diamonds daily when performing heavy activities.
Diamonds are hard, but they can be damaged. It is possible to break or chip a diamond. Breaking or chipping isn't the only way to damage a diamond. You can damage a diamond with chemicals that cause it to look dull and cloudy or discolor the stone until it is professionally cleaned.
Diamond is the hardest known material to date, with a Vickers hardness in the range of 70–150 GPa. Diamond demonstrates both high thermal conductivity and electrically insulating properties, and much attention has been put into finding practical applications of this material.
Diamond is the hardest natural material in the world. However, it's also brittle. Scientifically speaking, hardness measures the ability to resist scratching, nothing more. A gemstone's overall wearability grade takes hardness into account.
While there may not be many naturally-occurring materials out there that are stronger than diamonds, certain man-made metals like tungsten and steel have a higher tensile strength. That means a direct hit with an ordinary hammer can absolutely break a diamond.
Can a bullet break a diamond? Sure, bullets should have no trouble breaking diamond. Diamond's fracture toughness, 2.0 MPa (m^0.5), is below the fracture toughness of industrial ceramics like silicon carbide used in body armor. Bullets break that armor, too.
Diamonds are cut with specialized tools that make use of diamond tipped phosphor bronze or diamond dusted steel blades.
Diamonds will burn at about 1562°F (850°C). House fires and jewelers' torches can reach that temperature. A house fire caused the white, cloudy appearance of this diamond (left). The stone was recut to remove the burned area, reducing the diamond's size, but leaving no sign that it was ever damaged (right).
Diamonds have an isometric crystal structure, a specific gravity of 3.1–3.5, a Mohs hardness of 10, cling to a grease table, and glow under shortwave ultraviolet light in some situations. A combination of these traits is used to correctly identify an uncut rough diamond.