American rapper and actress Cardi B was weighed down with diamonds when she appeared on stage with an estimated $2.5m of bling.The 28-year-old wore dozens of dazzling high-end pieces for her performance at the annual Summer Jam hip-hop and R&B fest at the MetLife Stadium, New York.The most valuable single item was a 20-carat heart-shaped diamond ring from her husband Offset, also a rapper.Cardi B - real name Belcalis Marlenis Almanzar - also wore a Playboy chain by celebrity jeweler Elliot Elliante made with over 160 carats of VS1 diamonds and worth $400,000, according to the celeb news website PageSix.The rest of her collection also included: