Macy’s has launched a Valentine Day contest on social networking website twitter.com., asking consumers to "tweet" an original romantic note or writing for their Valentine, and stand a chance to win diamonds. The contest will span from February 1, 2010 through February 13, 2010, where the "Sweetest Tweet" post will win a diamond pendant and another lucky winner will be announced on Valentine Day for a three-stone diamond ring prize, reports say. %% Along with the contest promotion, the company also promoted gift options from its Effy Collection which included gold nd silver jewellery, and a ruby and diamond heart pendant necklace with matching earrings, reports say.