Posted Today At 1:24pm

Denise Truscello/WireImageKaty Perry was smiling Friday night in Las Vegas as she stepped out for her first U.S. public appearance since her split with husband Russell Brand just before New Year's. 

Katy was at the 1OAK club at the Mirage Hotel to support GiveLove.org, a charity founded by Patricia Arquette that helps Haiti's earthquake victims, and she walked down the red carpet sporting blue hair and a sexy black cocktail dress.  The event was co-hosted by her best friend, jewelry designer Markus Molinari, who told People magazine that the singer was doing "amazing" and she'd decided to attend the event because "that's what friends do."  At the event, which was also attended by David Arquette and Balthazar Getty,  Katy and J. Molinari jewelers, the company for which Markus works, presented a 50 thousand dollar check to GiveLove.

After the event, Katy tweeted, "Thanks to everyone who helped out w/the @givelove event at Mirage & 1 Oak LV. Go to http://www.givelove.org to see how u can MAKE a difference!"

Copyright 2012 ABC News Radio

Posted Today At 1:54pm

Frazer Harrison/Getty Images(LAS VEGAS) -- Katy Perry was smiling Friday night in Las Vegas as she stepped out for her first U.S. public appearance since her split with husband Russell Brand just before New Year’s.

Katy was at the 1OAK club at the Mirage Hotel to support GiveLove.org, a charity founded by Patricia Arquette that helps Haiti’s earthquake victims, and she walked down the red carpet sporting blue hair and a sexy black cocktail dress.

The event was co-hosted by her best friend, jewelry designer Markus Molinari, who told People magazine that the singer was doing “amazing” and she’d decided to attend the event because “that’s what friends do.”

At the event, which was also attended by David Arquette and Balthazar Getty, Katy and J. Molinari jewelers, the company for which Markus works, presented a $50,000 check to GiveLove.

After the event, Katy tweeted, “Thanks to everyone who helped out w/the @givelove event at Mirage & 1 Oak LV. Go to http://www.givelove.org to see how u can MAKE a difference!”

Copyright 2012 ABC News Radio