Diamond flower ring with white, black and cognac diamonds in 18ct gold, Takara Collection: Diamond flower ring in 18ct white gold with diamonds by New York designer Takara. This stunning designer ring is wonderfully unique; each of the flower's petals is covered with either black, white or cognac diamonds. The lower two layers of this ring have been finished with an oxidised rhodium to give the layers a subtle contrast. Measuring approximately 20mm in diameter, this fabulous cocktail ring has 2.83 carats total diamond weight, and is a must for any serious collection of fine jewellery.