Diamond is the most popular precious stone in existence. No substance on earth can compare to its amazing beauty, it has an unparalleled shine and brilliance. And what’s more? They are the hardest known substance you can find on the planet. That’s why they make the perfect timeless gifts, if you want to get someone a special and unforgettable gift, then get that special one a diamond necklace.
Have you ever pondered on why diamonds are so hard? Diamonds are hard and have high resistance to scratch, it is due to this extreme hardness and resistance to scratch, that it has become a very useful material in both fashion and industrial fields. Before you hit the market to buy a diamond necklace or ring, let’s find out what makes diamonds so hard. Today’s article will give you the best expert explanation about the hardness of diamond.
How is Diamond formed?
Diamond is a solid form of pure carbon formed under extreme pressure and high temperature deep within the earth’s crust. The name Diamond comes from the Greek word adámas which means invincible or unbreakable. It is made up of 99.95% carbon and 0.05% of trace elements. These trace elements can sometimes influence its colour and shape.
What makes a diamond so hard?
Diamonds are formed deep within the earth’s crust, about 100 miles below the surface where there is extreme heat and very high pressure. This high temperature and pressure cause the carbon molecules in the diamond to form a very strong covalent bond. Each carbon is strongly bonded to 4 adjacent carbon atoms forming a 3-sided pyramid structure. In diamonds, the 4 valence electron of each carbon atom takes part in the formation of a very strong covalent bond. The structure of the position of the carbon atoms in the covalent bond makes them sturdy in all directions.
The hardness of materials is usually compared using the Mohs Hardness scale. Mohs scale is numbered from 1 to 10, ranging from the softest to the hardest materials. On the Mohs scale Graphite which is very soft is numbered between 1 to 2, while Diamonds which are the hardest natural substance are numbered 10. Only diamonds as rated 10 on the Mohs scale, the closest to diamond is a conundrum, which is rated 9 on the Mohs scale. However, diamond is actually much harder than a conundrum. If the Mohs scale were to be in a linear form, Diamonds would have a value around 42 to 44.
Properties of Diamond
Besides being the hardest natural substance on earth, diamond also has an outstanding combination of physical, chemical, and mechanical properties which includes:
- Hardness
- High thermal conductivity
- Low thermal expansion coefficient
- Low coefficient of friction
- High electrical resistivity
- High strength
- High resistance to chemical corrosion
- Wide Optical transparency
- Biologically compatible.
Some interesting facts about Diamonds
Diamonds are the world’s most precious gemstones. Let’s take a look at some interesting facts about our beloved gemstone.
- As you know, diamonds are the hardest natural substance on the planet. Only a diamond can be used to cut a diamond.
- Diamonds are carried to the earth’s surface through volcanic activity
- Diamond isn’t the only gemstone made of one element—carbon.
- Some ancient cultures believe the diamond to be a symbol of courage and strength.
- The largest rough diamond was found in 1905, it was named Cullinan weighing 3,106 carats.
- The first woman to wear a diamond engagement ring is Mark of Burgundy, it was given to her by Archduke Maximilian of Austria
- In 2004, scientists discovered a planet called “55 Cancri e”, they believe one-third of this planet is made of diamond.