It is interesting to note that something that is almost transparent can alter the look of a watch. There are typically three primary types of materials used in a watch crystal. They are:
(Photo: Zeppelin 7036-1)
- Acrylic/plexiglass – the softest type and most scratch-prone. This material can be polished using certain creams and offers the most vintage appeal of the three.
(Photo: The Electricianz Cazino)
- Mineral – the choice for lower priced watches. Most cost effective to replace and sufficiently robust for most instances. Definitely not as scratch resistant as sapphire.
(Photo: Tacs Automatic Vintage Lens II)
- Sapphire – the most luxurious and durable of the three. For most serious watches, this is the material of choice and is seen as a compulsory addition.
Essentially there are 3 shapes to watch crystals with each of them providing a different aesthetic to the watch especially in the way it magnifies the dial. The flat crystal is a straightforward crystal that ensures that a watch remains as slim as possible. The domed crystal adds a little height to the case of the watch but offers a vintage look to the watch and may be more suited to rounded cases. The boxed crystal is like a domed crystal where it slopes down towards the edge and falls off sharply at the edges. This type offers the most retro/vintage appeal and magnifies the details of the dial towards the edges.
Finally, the presence of anti-reflective coating on a crystal may eliminate light reflections and this will enhance the legibility of a dial. Should a crystal be coated on both sides, inside and out, then the dial shall be clearly seen and may look almost naked as though without protection. Of course, such coating that sits on the outside, may not be as durable as the crystal it is protecting. Most of them are definitely easier to scratch than materials such as sapphire.