23ct Riviera Platinum Multicolor Diamond Necklace. CJ Charles Riviera necklace of platinum and 18k yellow and rose gold set with pink, yellow and white diamonds. The 48" necklace is set with pink diamonds weighing a total of 0.94cttw, yellow diamonds of 4.27cttw and white diamonds of 17.62cttw. The necklace clasp is set with pink diamonds weighing a total of 0.13cttw, yellow diamonds of 0.16cttw and white diamonds of 0.23cttw. The total diamond weight in the necklace is 23.35cttw.