What are the differences in structures of diamond and graphite? And how do they relate to their chemical properties and uses?

Although both are... 1. Alltotropes of carbon, i.e. both are composed of carbon. 2. Giant covalent structures. Which are composed of non-metal aroms, held adjacently by covalent bonds. These atoms are arranged in a regular repeating strucutre known as a lattice. The high quanity of bonds : surface area ratio makes both carbon and diamond very strong. Differences 1. Diamond: each carbon atom bonds to 4 other carbon atoms, WHILST, Graphite: each carbon atom bonds to 3 other carbon atoms. Thus, diamond bears more of a tetrahedral structure, whereas graphite takes the form of layers. The presence of layers means that atoms can slide over each other easily. Thus, graphite's use as a lubricant. The 4th electron isn't involved in bonding and thus is free to move in between layers and is able to carry electricity. Hence, graphite is a weak conductor of electricity. 3. Diamond has stronger intramolecular bonds than graphite. As a result more energy is required to overcome the bonds existing in diamond. Therefore, diamond has a higher boiling point. Also, diamond is used for drilling, cutting, etc which is indicative of it's strength.