The variety of watch glasses
When selecting a new watch, the fashion-conscious buyer essentially pays attention to a good look and a chic design. However, those who are not exclusively interested in looks often check other parameters as well. These include, for example, the movement, the type of leather, the other features but also the glass. The glass of the wristwatch protects the dial from unpleasant knocks that can happen naturally in hectic everyday life. The dial of a wristwatch is the centre of every timepiece, as the dial is by far the most frequently looked at. The filigree hands, whether second, minute or hour hands, features such as date or moon phase. The dial should be well protected behind the matching glass. These glasses can be of different quality and essentially distinguish the watch experts in three groups. These are plastic glasses, mineral glasses and the high-end product sapphire glasses. Each of these glasses offers different properties and is used in different areas of application.
Plastic glass – basic material but robust
Plastic glass is the cheapest option of the three glasses mentioned, which are used for watches. The plastic used is PMMA, which means polymethyl methacrylate and is both lightweight and relatively impact-resistant. Synonyms that are used for the material but are the same are, for example, plexiglass or acrylic glass. The night part of this watch glass is mainly the low hardness of the plastic, which is why watches with this glass are more prone to scratches than other glasses.
Mineral glass – Not only window glass
Mineral glass is just as difficult a chemical term as plastic glass. The chemical name for watch glass is silicon oxide, abbreviated SiO2. It is not, as is often wrongly described, typical window glass. Good mineral glasses are chemically hardened in a complex process and are therefore often harder and therefore more scratch-resistant than plastic glass. But there are dangers here too. If the glass breaks, fragments of the watch glass can get into the movement and cause damage.
Sapphire glass – wristwatches at the highest level
The primus among watch glasses is called sapphire crystal and is without doubt the hardest of the watch glasses. HENRI BENETT watches are also equipped with sapphire crystal and thus offer the highest quality. The Verneuil process, which is used for the synthetic production of sapphire crystals, is a crucible-free flame melting process for the production of synthetic gemstones. The process is named after the chemist who published the Verneuil process in 1902. Sapphire glass is mainly used for luxury watches, but companies such as HENRI BENETT, which are active in the fashion watch sector, also rely on the high quality of the material.