Alexander the Great (?), ring: mid-16th century; cameo: early Hellenistic 4th century B.C., probably Italian, turquoise, enamel, gold, ring setting, overall: 1 x 1 1/16 in. (2.6 x 2.7 cm); visible cameo (confirmed): 11 x 9.6 mm. This vibrant carving has previously been described as made of glass and as a product of the French Renaissance, but it is in turquoise, a rarity in cameos of any period. That it is reputed to have been in the Este collections may make an Italian origin likelier.