A diamond is cut at many angles to make it sparkle. Getty Images

A diamond is cut at many angles to make it sparkle. Getty Images

Diamonds are formed deep under the ground.

The diamonds being mined today are hundreds of millions of years old. They formed long ago, deep inside the Earth and have been moved closer to the surface by volcanic eruptions.

Mining for diamonds

Diamonds are mined in open pit mines like this. Getty Images

Diamonds are mined in open pit mines like this. Getty Images

Diamonds are mined in open pit mines. The open pit can be kilometres long and a kilometre wide, and cover many hectares.

Soil and rock is removed so that rock containing diamonds can be collected.

Explosives are used to break open the rock. Tonnes of rock is taken by trucks to a crusher.

Many tonnes of rock has to be mined and crushed to get just one small diamond.

Rough uncut diamonds: this is what the look like when mined. Expert cutters cut and polish them so they look like what we know as diamonds. ©iStock

Rough uncut diamonds: this is what the look like when mined. Expert cutters cut and polish them so they look like what we know as diamonds. ©iStock

 

Diamonds are also mined underground. Tunnels are dug deep into the earth and miners drill into the rock to get diamonds.

An interesting fact:

The cutting part of the drills used by diamond miners are made of diamond!

 

Diamond mining and the environment

Diamond mining can be harmful to the environment:

  • Air is polluted by dust from open pit mines.
  • The land is affected by the removal of soil and plants when mining takes place.
  • Dirt washes into rivers and streams from mine sites.

Miners might try to reduce the effects of mining on the environment but accidents happen and some miners don't take enough care to reduce the damaging effects of mining on people and the environment. 

Diamond cutting

Once the diamonds are found they must be cut and polished so that they can be used to make jewellery. A diamond cutter cuts and polished the many sides (called facets) of a diamond. Diamonds are cut to make them reflect light, shine, and sparkle.

Did you know? 

Diamonds were first mined in India over 2800 years ago.

The top diamond producing countries are Australia, Zaire, and Botswana. 

 

Synthetic diamonds

Diamonds can be made in factories. Carbon is squeezed in machines at high temperature and pressure to make diamonds that are known as synthetic (say sin-thet-ic) diamonds.

Synthetic diamonds can't be used for jewellery. They are used in industrial tools to cut, grind and bore into other hard materials.

Watch a video about how diamonds are formed

 

Read about the ten most famous diamonds in the world:

http://www.studiosoft.it/jewelryworlds10.htm

Watch this video about the mining, cutting and sale of diamonds