Multi-platinum recording artists N’Sync recently auctioned an Elara Diamond cross necklace to benefit their charity, Challenge for the Children. Designed exclusively for the charity, the pendant incorporates woven platinum and Elara diamonds, the only gemstones in the world to be awarded a U.S. copyright.

The necklace was displayed at the kick-off party for the fifth annual Challenge for the Children weekend on July 18 in Miami Beach, Fla., attended by a long list of celebrity guests. The event included a Celebrity Skills Challenge on the beach on Saturday, July 19, followed on Sunday, July 20, by a basketball game between the Daze and Knights celebrity team at the Office Depot Center in Fort Lauderdale. Tickets for these events are available through TicketMaster.