The 18.4-carat “Rockefeller Emerald” will be the highlight of Christie’s New York Magnificent Jewels auction on June 20. The emerald ... combination of size, provenance, absence of treatment ...

In addition to the main diamond, 66 “satellite” diamonds have been polished from the rough, ranging in size from under a carat to more than 26 carats. Each diamond is inscribed with “Graff ...