Roulette or Possession

A part turns on each ring, though not on the same axis. Possession's second band spins around the finger like a wheel on an axle, and Piaget has been dressing it since 1990 in diamonds, malachite, turquoise and chased gold. Roulette flips instead. Its small circle of brilliant-cut diamonds swivels across the band to show a second face, diamonds again on the ring, polished gold on the earrings. Boodles publishes no year or designer for it, and scales the same circle up to collars and pink-diamond bracelets.