There’s an old song that suggests “diamonds are a girl’s best friend”. But, as you’re about to discover, diamonds are probably better described as the world’s best friend.
They might sparkle nicely and look great in an engagement ring, but diamonds can be used to brighten up more than just your ring finger.
CARBON SKELETON
Diamonds are formed from the element carbon.
Burn a match and the black stuff that remains at the end of the stick is carbon.
Carbon can be found on Earth in three different crystalline forms. First, as a diamond – a hard, clear, extremely valuable crystal. Second, carbon can be found as graphite – a soft black, slippery material. Finally carbon also forms the mineral fullerite – with each perfectly round molecule consisting of exactly 60 carbon atoms.
CRUSHING PRESSURE
To make a diamond, carbon has to be crushed at just the right temperature and pressure. Such conditions occur in the hot molten rock of the Earth’s mantle around 160km’s beneath the Earth’s crust.
Most diamonds that are found on Earth were created millions (if not billions) of years ago, and have been brought to the Earth’s surface through eruptions of the Earth’s mantle.
But not all the diamonds found here were created on Earth. Some have arrived from outer space!
Microscopic diamonds that have formed in space (both within and outside our solar system) have been found in meteorites that have hit the Earth. Other, larger diamonds have been created when meteorites have collided with our planet.
WORKING DIAMONDS
No matter how or where they’ve been created, diamonds retain one stunning property that allows them to be used for all sorts of purposes – they are incredibly hard. In fact, they are the hardest material known to humankind!
A diamond’s hardness results from the way its carbon atoms are arranged. Each carbon atom is linked to four other carbon atoms in a tetrahedral (triangular pyramid) formation. The resulting latticework creates an incredibly rigid, incredibly strong, and incredibly useful structure.
Because of their hardness, diamonds have been used to create or coat many cutting, grinding or drilling tools.
For this same reason, diamonds are able to cut other hard materials that are used to cut, grind or drill.
But it’s not just diamonds brute strength that is being exploited by scientists and technologists. Diamonds also have a very high melting point. Because of this, some scientists are exploring the possibility of replacing silicon-based computer chips with diamond-based computer chips.
Computing power requires electricity, and electricity creates heat. A diamond-based computer chip will be able to cope with much higher temperatures than a silicon-based chip, potentially allowing much greater computing power.
Scientists are even exploring ways to use diamond dust to create lighter and cheaper display units for flat screen televisions as well as other devices.
EVER AFTER
It would seem that such a hard substance would be difficult to imitate. But the first artificial diamonds were created on 16 February 1953, by a team of scientists lead by Baltzar von Platen, the man who also invented the fridge.
The team managed to squash and heat a sample of graphite until it turned into diamond crystals, each around the size of a grain of sand.
At least one company has used this idea to provide a bizarre service that uses the carbon from a person’s cremated ashes to make diamonds. These diamonds can then be kept and even worn by others to remember and celebrate the person they were created from!
The largest diamond found on Earth is the Star of Africa. Discovered as a 3106-carat stone, it was cut into nine large and 96 smaller stones. The largest, at 350 carats, is the centrepiece of the British crown jewels.
Eighteen per cent of your body weight is carbon, which means it is possible to turn yourself into a diamond – but only after you die, of course!
