The newest addition to this movement is the LEED Gold certified International Motorsports Center, better known as the headquarters building for NASCAR.

FORBES: NASCAR's headquarters earns LEED Gold certification

More than a decade after winning Season One, Clarkson continues to grow her career, and her bank account, with the help of gold-certified album Stronger, a mentor role on The Voice, a Toyota commercial and a lucrative tour.

FORBES: Top-Earning American Idols 2012

Actually, gold bullion is any form of pure, or nearly pure, gold that has been certified for its weight and purity.

FORBES: Getting Into The Gold Market