For instance, graphite and diamond are both made of carbon, but the difference in the crystalline arrangements of their carbon atoms means that graphite conducts electricity while diamond is a good insulator.

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Their results suggest 55 Cancri e is largely composed of carbon (in the form of graphite and diamond), iron, silicon carbide, and, potentially, silicates.

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Elemental carbon had long been thought to exist in only three physical forms: graphite, diamond and an amorphous form, of which charcoal is an example.

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This body, known as 55 Cancri e, "is likely covered in graphite and diamond rather than water and granite, " according to astronomer Nikku Madhusudhan from Yale University.

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In the same way, the pattern of holes in a crystal fibre can create the equivalent for light of a graphite core and a diamond cladding.

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Think of it this way: The graphite in a pencil and a diamond differ only in how their carbon atoms are arranged.

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The substance, which is derived from graphite, is stronger than diamond, more conductive than copper and more flexible than rubber.

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