Blue in the face
What comes to mind, when thinking about glass? Of course, clearness, mirrors, opacity, fragility… exactly - fragility. How many times have you dropped a drinking glass, a smartphone, a watch, and the glass on the respective items exploded into a menacing pool of crystal shards? You probably haven’t even attempted to count the number of times that happened. Or you're one of those units that are extremely lucky and have a quick hand. For the rest of us, less fortunate, there is a solution and its name is sapphire glass.
From now on, the new standard for our watches will be sapphire glass. Synthetic sapphire, which has the same properties as the natural version of the gem, is made by putting aluminum oxide powder under extreme heat and pressure. Internal stresses are released thanks to further high-temperature processing and then the result is refined into layers of sapphire glass - a translucent material more durable than gorilla glass. In fact, sapphire glass was considered to be used in smartphones, tablets etc., but most brands deemed the cost of production too high for a product with such a short lifespan. Furthermore, many watch brands use just sapphire glass coating. While it provides a more durable face, it's not as effective as ones that are entirely made from sapphire. The coating that we use for our timepieces is anti-reflective, which means that more light goes through the glass, making the hands and marks clearly visible.
What does sapphire glass mean for our premium watches, though? Well, unless you have a diamond or another sapphire lying around, your watch’s face will be highly scratch-resistant. If we refer to Moh’s scale of mineral hardiness, sapphires have a value of 9, whereas diamonds - 10. Only the hardiness and direct contact of a diamond can produce scratches on the glass. Furthermore, the material is not just hard, it’s strong, too. As I’ve mentioned before, synthetic sapphire has the same properties as its naturally-occurring counterpart. Sapphires have a compressive strength value of around 2000MPa (megapascals). For reference, stainless steel has around 170MPa. With the strength of stainless steel tenfold, it’s safe to say that this glass is resilient.
So there you have it. Sapphire glass that is commonly used for bullet-proof windows in armored vehicles, visors in the army’s combat gear, and other military tech, will be the faces of all our premium timepieces from now on. The next time you’re thinking about getting a sturdy watch that will last you a lifetime - you know where to find them..