Rado 'DiaStar Ceramica' analogue quartz wristwatch, 1998.
© Science Museum / Science & Society Picture Library
The specific importance of this watch is its case and bracelet, which are made of very hard ceramic. The crystal - the transparent cover over the dial - is made of sapphire, also virtually scratch-proof. Rado, now part of the Swatch group of Swis watch manufacturers, made its first scratch-proof watch, the 'DiaStar 1' in 1962. In 1996 they made the 'Concept 1' wristwatch cased in polycrystalline diamond.