An emerald, colored diamond and diamond necklace and pair of pendant earrings. photo Bonhams

the necklace designed as nineteen oval emerald and round brilliant-cut diamond clusters each with yellow diamond floral cluster spacers; a pair of earrings en suite; estimated total emerald weight for the set: 48.95 carats; estimated total diamond weight for the set: 18.65 carats; mounted in eighteen karat gold; necklace length: 15 1/2in. (colored diamonds not tested for origin of color). Estimate: $35,000 - 45,000

An emerald and diamond ring, Bulgari. photo Bonhams

centering a hexagonal-cut emerald flanked by three triangular-cut diamonds and completed by baguette-cut diamond seven-stone shoulders; signed Bvlgari; emerald weighing approximately: 2.70 carats; estimated total diamond weight: 4.30 carats; mounted in eighteen karat gold; size 5 1/2 - Estimate: $35,000 - 40,000

An emerald and diamond ring. photo Bonhams

centering a cut-cornered square-cut emerald, weighing 12.39 carats, within a marquise-cut diamond surround; estimated total diamond weight: 1.50 carats; mounted in platinum; size 5 3/4 - Estimate: $25,000 - 35,000

Accompanied by GIA report #112790449 dated March 12, 2010, stating the emerald as: Colombian origin, minor clarity enhancement.

An emerald and diamond ring. photo Bonhams

centering a cabochon emerald, weighing 8.81 carats, within a bombé mount of pavé-set circular-cut emeralds, and completed by round-brilliant-cut diamond-set shank; mounted in platinum; size 6 - Estimate: $20,000 - 30,000

Accompanied by AGL report #CS38610, dated September 28, 2006, stating the emerald as: classic Colombian origin, faint to moderate clarity enhancement.

A pair of antique emerald and diamond clip brooches, circa 1880. photo Bonhams

each centering an oval-shaped cabochon emerald within a double-row surround of old mine and old European-cut diamonds; estimated total diamond weight: 15.00 carats; estimated total emerald weight: 25.00 carats; mounted in silver topped gold - Estimate: $15,000 - 20,000

A Colombian emerald and diamond ring. photo Bonhams

centering a rectangular-cut emerald, with baguette-cut diamond channel-set six-stone shoulders; emerald weighing approximately: 7.80 carats; estimated total diamond weight: 2.00 carats; mounted in platinum; size 5 3/4 - Estimate: $8,000 - 10,000

Accompanied by GIA report #6107257446, dated September 25, 2008, stating: natural emerald, Colombian origin, moderate clarity enhancement.

A pair of emerald and diamond earrings, Bulgari. photo Bonhams

each of hexagonal outline, centering a round cabochon emerald within a surround of round brilliant-cut diamond detail; each signed Bvlgari; mounted in eighteen karat gold - Estimate: $3,000 - 5,000

A pair of coin, diamond and emerald earclips. photo Bonhams

each centering an ancient coin with pavé-set diamond and oval cabochon emerald detail; mounted in eighteen karat gold - Estimate: $3,000 - 5,000

Bonhams. Fine Jewelry. New York, San Francisco and Los Angeles, 19 Apr 2010 at 13:00