Rare Renaissance Gold and Type IIA Diamond Ring, 16th-17th Century AD
A slender D-section gold hoop with graduated rosettes to the shoulders, scrolls supporting a cupped bezel with egg-and-dart modeling to the rim, open to the underside; inset baguette-cut Type IIa ‘first water’ diamond; engraved areas were once enameled black as was customary for that period, trace enamel in extant. 3.78 grams, 23mm overall, 16.04mm internal diameter. Rare.
The stone was sourced from the Golconda mines, Hyderabad, India, which ceased production in 1725. It was subjected to analysis at EGL USA in New York in October 2016 and certified ‘Type IIA and not treated’. Type II diamonds have no nitrogen impurities. Type IIa diamonds comprise 1-2% of all natural diamonds; they are often entirely devoid of impurities and are usually colorless. The underside of the ring’s bezel was probably cut away in the 19th century to improve the appearance of the stone.
At the time of its cutting, the diamond would have been described as a ‘diamond of the first water’, a reference to its perfect clarity. The term went out of use for defining the color, clarity and internal cleanliness of diamonds when newer, more scientific grading systems came into use. Golconda stones of this purity are very rare.