Half Moon Watch Seiko - Etsy。This vintage timepiece is a Seiko \"Half Moon\" (also known as the Seiko Rivoli), a cult-classic women\'s watch from the late 1980s and 1990s. It is highly sought after by collectors for its unique, asymmetrical crescent-shaped case. Model Number: Commonly identified as the 2E20-7309 or 2E20-7399. Design: Features a black dial housed in an 18ct gold-plated stainless steel case with a silver-tone bezel accent. Gemstones: The bezel is typically accented with six real diamonds (three on each side). Movement: Japanese quartz movement. Band: Gold-tone linked bracelet, often adjustable by removing links. It needs a new battery and cleaning so priced accordingly.