Shares of his eponymous firm, Rajesh Exports, India's largest manufacturer and exporter of gold jewelry, zoomed in July when it bought Swiss gold refiner Valcambi for $400 million in an all-cash deal. Mehta started company in 1989 with older brother Prashant, who is now managing director. They, along with 2 other siblings, own 54% of the firm. Family portfolio includes valuable gold mines in Africa. Son Siddharth works as chief strategist.