virole brisee
(French) Segmented collar for imparting edge devices as on some of Droz's patterns for Boulton (1788), and as on St. Gaudens gold coins beginning in 1907.
Source: Breen Encyclopedia
(French) Segmented collar for imparting edge devices as on some of Droz's patterns for Boulton (1788), and as on St. Gaudens gold coins beginning in 1907.