Sapphire crystal generally is used to produce surface glass ofwrist watch. It is a kind of synthetic glass with hardness only second to that of diamond. It has characteristics of scratch-resistance and wearing resistance. However, Beijing Watch makes a breakthrough to use this material to produce main plate of movement. With combination of hollowed-out design of dial plate and double tourbillon structure movement, the mechanical operations between movement wheel gears are explicitly visible through transparent rear bottom cap, which brings more transparency and dynamic aesthetic conception to wrist watch.

For the reason of relatively fragile texture, sapphire crystal breaks easily. It proposes extremely high requirement on production of crystal plate. However, it is impossible for ruby to be directly embedded on sapphire crystal. It is required to make a gold-material sleeve for ruby bearing. The polishing process is extremely particular about watch-maker’s craftsmanship. Crystal plateconsequently becomes precious hand-made artwork in watch-making techniques.