Way back when you were at school, it is very likely that you would have come across the term ‘pencil lead’, referring to the central core of a pencil that is able to produce marks on paper and other material. In fact, rather than referring to the chemical element and heavy metal, lead, this central core is most commonly made from graphite mixed with clay. The mistake arose when it was first discovered, at which point because it is a form of carbon and contains a similar molecular make up to other members of the carbon group (though primarily due to the visual similarities), it was thought to be a form of lead.Graphite is a mineral that naturally occurs in metamorphic rock in different continents of the world, including Asia, South America and some parts of North America. It is formed as a result of the reduction of sedimentary carbon compounds during metamorphism. Contrary to common belief, the chemical bonds in graphite are actually stronger than those that make up diamond. However, what defines the difference in hardness of the two compounds is the lattice structure of the carbon atoms contained within; diamonds containing three dimensional lattice bonds, and graphite containing two dimensional lattice bonds (layers of carbon sheets). While within each layer of graphite the carbon atoms contain very strong bonds, the layers are able to slide across each other, making graphite a softer, more malleable material.Extensive research over hundreds of years has proved that graphite is an impressive mineral showing a number of outstanding and superlative properties including its ability to conduct electricity and heat well, having the highest natural stiffness and strength even in temperatures exceeding 3600 degrees Celsius, and it is also highly resistant to chemical attack and self-lubricating. However, while it was first identified over a thousand years ago and first named in 1789, it has taken a while for industry to realise the full potential of this amazing material.
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