Mystery setting

Van Cleef & Arpels patented its Mystery Set in 1933. Each ruby or sapphire is cut with fine grooves at its base and slid onto a network of thin gold rails, so the stones sit edge to edge with no visible metal on the surface. The result is a continuous field of color.

A single piece can take hundreds of hours, and only a small number are made each year. Vintage mystery-set jewels are among the most valued of the house.

What to look for

Look closely for chipped, cracked or replaced stones and for uneven areas in the surface. Repairs require specialist work.