Value of Diamonds

Value of diamonds are measured by four characteristics known as the 4C's Letter. The 4C's Letter relate to a diamond's Cut, Colour, Clarity and Carat weight. The quality of a diamond is measured by its Cut, Colour and Clarity. The Carat weight measures the size of the diamond. Of all the 4C's Letter, Cut is the characteristic directly influenced by man; Colour, Clarity and Carat weight are all dictated by nature. 

Most natural diamonds are formed at high-pressure high-temperature conditions existing at depths of 140 to 190 kilometers (87 to 120 mi) in the Earth mantle. Carbon-containing minerals provide the carbon source, and the growth occurs over periods from 1 billion to 3.3 billion years (25% to 75% of the age of the Earth). Diamonds are brought close to the Earth surface through deep volcanic eruptions by a magma, which cools into igneous rocks known as kimberlites and lamproites. Diamonds can also be produced synthetically in a high-pressure high-temperature process which approximately simulates the conditions in the Earth mantle.