The sorts of diamonds can be subdivided based on the quality criteria for diamonds (colour, weight, purity and cut). The different cuts (brilliant, princess cut, emerald cut, heart-shape, Asscher cut, cushion cut, radiant cut, oval cut, marquise, pear-shape, cabochon, baguette, trilliant) determine the appearance and sparkle of the stone. There is also the colour aspect. Blue, yellow, purple, pink, red, brown, green and black diamonds are rare and therefore also valuable.