Bangles were spotted on women in prehistoric Algerian cave paintings and unearthed in ancient Egyptian archaeological digs. How, then, do you reinvent the accessorial equivalent of the wheel? Cast it in vintage green Bakelite and stud it with amethyst and pink tourmaline, the way Mark Davis did. Cut it from blue jade and sprinkle it with diamonds and sapphires à la Fred Leighton. Mold it from candy apple-red enamel and pale pink coral like James de Givenchy for Taffin did. Then wear one, or all eight, at a time. From top: Roberto Coin, $9,000; 800-853-5958. Elizabeth Rand, $12,500; 212-754-1227. Fred Leighton, $85,000; 212-288-1872. Taffin by James de Givenchy, $45,000; 212-794-0308. John Hardy, $995; 866-454-2739. Gurhan, $2,830; 877-447-4692. Mark Davis, $3,200; 212-826-8900. Yossi Harari, $1,965; 212-872-2518.