if you've purchased a diamond on these dates (1/1/1994 - 5/31/2006), you may be entitled to a refund. check this out :
http://articles.moneycentral.msn.com/smartspending/consumeractionguide/buyadiamondgetarefund.aspx
or here :
https://diamondsclassaction.com/
http://articles.moneycentral.msn.com/smartspending/consumeractionguide/buyadiamondgetarefund.aspx
or here :
https://diamondsclassaction.com/