Nickel is a naturally occurring chemical element with the chemical symbol of Ni. It has an atomic number of 28. It is a hard silvery-white substance, known as a transition mineral. It is highly reactive with oxygen, which means that it isn’t found in its free form on the Earth’s surface. Native nickel is most often found with iron and it is thought that the core of the earth is made from a nickel-iron mixture. Nickel is used mostly in its alloy form.
How is nickel mined?
Nickel has to be mined from under the ground. Both open pit and underground mining is used to extract nickel from under the ground. The vast majority of nickel is mined in Russia, Australia, Canada and New Caledonia. Open pit mining is where the top layers of the soil are removed with heavy machinery to expose the seams of rock underneath. These rock seams are then dug out and broken up to be refined. Underground mining is when tunnels are dug under the ground and the ore is mined from the tunnel walls. This is sometimes done with special tools, but more commonly with explosives.
As nickel is commonly found with other metals, especially iron, it is mined as an ore that needs to be separated and refined to produce nickel. Nickel is often extracted from its ore by roasting at high temperatures. In some cases this is enough to separate the nickel in other cases strong chemicals are used to separate the ore. Nickel is also refined using electro refining. In this process the ore is placed in a nickel salt solution and an electrode placed in the mixture. The nickel is attracted to the cathode and separated from other metals.