Diamond

Diamond is the element carbon in a rigid cubic crystal lattice, the hardest natural material known and the mineral that defines 10 on the Mohs scale. Pure diamond has no colour; nitrogen tints it yellow or brown and boron blue, radiation turns it green, distortion of the lattice gives some brown, pink and red stones, and 'black' diamonds owe their darkness to dense inclusions. Most natural diamonds grew between one and three and a half billion years ago, deep in the Earth's mantle, and were carried up far later by kimberlite and lamproite eruptions. The name goes back to Greek adamas, meaning untamed or unbreakable. India is thought to be where diamonds were first recognised and mined, and in 1772 Lavoisier burned one in oxygen to show that it is made of carbon. About four in five mined diamonds are unfit to be gems and go to industry for cutting and grinding, and laboratory-made diamond is now produced in enormous quantities. Cunningham ties diamond to the Sun and fire and uses it for spirituality and meditation, courage and strength, protection, peace, reconciling quarrelling lovers, fidelity and healing; worn at night, he says, it eases nightmares and brings sleep. Hall treats it as a symbol of purity, wealth and fidelity and an amplifier of energy, while warning that it magnifies negative energy as readily as positive.