Program aims to educate young consumers about mined stones’ positive qualities.
Piece rakes in $688,000 at London auction against expected price of $242,000.
Unmounted stone has a $550,000 high estimate at upcoming sale.
A Fabergé diamond and aquamarine necklace from 1911 could fetch up to $600,000 in New York.
Pinks and blues make up top five lots, including one likely to fetch over $6 million.
James Marks will fill the role, starting June 1.
Piece has upper estimate of $242,800 at London sale.
Piece was top lot at $11.7 million Geneva Fine Jewelry sale.
Many items surpassed estimates at Geneva High Jewelry auction.
A. Lange & Söhne timepiece from 1916 will lead May 10 auction.
Black-diamond ring sells for $122,499, making six times its high estimate.