A pair of diamond and black diamond pendant earrings. photo Bonhams

estimated total diamond weight: 7.40 carats; mounted in eighteen karat white and blackened gold; length: 1 9/16in. (black diamonds not tested for origin of color) - Estimate: $4,500 - 6,500

A black diamond and diamond ring. photo Bonhams

centering a reverse-set black diamond, weighing approximately 10.85 carats; mounted in eighteen karat white gold; size: 7 (black diamond not tested for origin of color) - Estimate: $3,000 - 4,000

A pair of colored diamond and diamond pendant earrings. photo Bonhams

estimated total diamond weight: 7.00 carats; mounted in eighteen karat bicolor gold; length: 1 1/2in. (colored diamonds not tested for origin of color) - Estimate: $2,750 - 3,750

A diamond and black diamond ring. photo Bonhams

estimated total diamond weight: 1.90 carats; mounted in eighteen karat gold; size: 7 (black diamonds not tested for origin of color) - Estimate: $1,800 - 2,500

Bonhams & Butterfields. Quail Jewelry and Watches, 13 Aug 2010. Quail Lodge www.bonhams.com