Crystal Composition
Watch crystals are made with three different materials: 1. Plexiglass (a clear, lightweight plastic). 2. Common glass - like that used for windows, and usually referred to as "mineral crystal". 3. Synthetic sapphire. Some crystals are made of both mineral and sapphire glass. Seiko, for example, makes some watches with crystals made of mineral glass covered with a layer of synthetic sapphire. Seiko calls this composite material "Sapphlex" or "Hardlex".
En cristiano, "hardlex" y también "sapphlex" es como Seiko llama a un cristal mineral recubierto de una capa de zafiro sintético.
Saludos,
Juan Andrés