For the first time in decades, the sales of diamonds have been declining as the colored gem trade has increased in sales. Rubies, sapphires, and topaz stones have become increasingly popular when choosing engagement rings due to many reasons. Colored gems are less expensive and celebrities have stirred up a great interest in these colored gems. For the first time since 2008, diamond prices are declining.
VS 
Personally, I find colored gems much more intriguing and special than diamonds. As the colorful gems are in fact much more unique than diamonds, have consumers finally realized that diamonds are not worth their price? I believe not. The decline in diamond sales have a large part to do with celebrities suddenly sporting these colored gems instead of diamonds. This arising trend in celebrities has caused a shift in consumer taste. In the society we live in today, celebrities hold a certain power and influence to get a product sold, hence the gargantuan amount of money that is spent on celebrity endorsements. I believe celebrity endorsement is one of the most efficient marketing strategies in advertising a product due to their strong connections with viewers. If celebrities such as Kate Middleton and Jessica Simpson had been wearing diamond rings instead of sapphire and ruby engagement rings respectively, I believe that the colored gem’s popularity would not have rose to the point where the diamond industry is threatened.
Source: http://www.businessweek.com/articles/2012-11-15/maybe-diamonds-arent-forever#p1