A good question! There is nothing more unsightly than a luxury watch with a huge scratch across the face. Luckily most luxury watch crystals (the transparent cover that protects the watch face) are synthetic sapphire. Sapphire is an impressive No. 9 on the Mohs scale of Hardness. This scale is the preferred method used to rank Gemstones and other minerals according to their hardness. The scale is graded from 1 to 10; 1 being the softest (talc) and 10 being the hardest (diamond)
A fingernail is 2.5 and pure gold, silver and aluminum ranges is a mere 2.5; glass is between 5.5 and 6.5 and emerald is 7.5. Both Ruby and Sapphire tie at No. 9.
The rule of the thumb is that any higher digit on the scale can scratch any lower digit. A diamond can scratch just about anything, whereas talc can be scratched by anything.
Sapphire crystal is therefore one of the hardest materials on the earth, and as a result scratch resistant to any material lower on the Mohs scale. Being a whopping 9 means that the crystal is quite protected .However, before you go about testing the watch yourself, remember that since sapphire crystal is so hard, it is also brittle, and can shatter or chip more easily than some of the other watch crystals like Plexiglas or mineral glass. In addition some man made materials used to make simulated stone surfaces for furniture and walls comprise of incorporated silicon carbide. This material ranges between 9 and 10. The watch wearer should be careful not to scrape the watch against this type of wall or furniture, as this could result in a scratch of the watch crystal.
Although your watch is scratch resistant , it does not mean that the watch crystal is necessary sapphire crystal. Some watch crystals are coated with a hard substance that makes them scratch resistant.
As with any luxury watch, good maintenace and care is part of the longevity of your watch. So if you looking to buy a:
TAG Heuer - Cartier - Movado - Ebel - Concord - Breitling - Audemars Piguet - Corum - IWC - Longines - Omega - Vacheron Constantin
