A bold and exceptional signed ring by Hammerman Brothers, the celebrated New York diamond jewellers, in 18ct yellow gold, c.1970s. The ring is formed in the bombé style — a deeply domed, convex form that curves dramatically over the finger — set with five rows of carré-cut diamonds totalling an estimated 6 carats. The carré cut, a square step-cut with open corners, was a favoured stone format in the bold, architectural diamond jewellery of the 1960s and 1970s, its clean geometry and broad, open table creating a surface of continuous, uninterrupted brilliance across the dome of the ring. Hammerman Brothers, active in New York from the mid-20th century, were known for exactly this kind of confident, high-diamond-weight jewellery, and a signed piece carries the full weight of that reputation. Note: one stone has been replaced with a princess-cut diamond. Hallmarked 18ct gold.

The Details

• Circa: 1970s
• Estimated total diamond weight: 6 carats (carré-cut; five rows)
• Hallmarks: 18ct gold
• Maker: Hammerman Brothers, New York (signed)
• Note: One stone replaced with a princess-cut diamond