What is the watch’s hard glass? The most popular types of watch glasses today

There are many different types of watch glass on the market today. However, hard glass is considered the most popular type because of many outstanding advantages. The following article will help you better understand the concept of hard glass, how it is manufactured, and what are its outstanding uses.

What is the watch’s hard glass? What is hard glass made of?

The watch’s hard glass is glass that has been mixed with inorganic compounds to increase its hardness , strength and heat resistance .

To create hard glass, the manufacturer must use tempered glass made from lime glass, then fused with caustic soda and necessary minerals at high temperature.

This mixture will be cooled suddenly (or soaked in potassium nitrate solution). This will help the glass increase its hardness and strength, and when broken, it will also create non-hazardous glass fragments.

Uses and advantages of watch face hard glass

• Due to its high strength and heat resistance, the glass is less prone to cracking and breaking . At the same time, due to the special tempering process under high temperature and rapid cooling, the broken glass surface is not dangerous to the user.
• The price is cheaper than other watch face materials. For example, compared to Sapphire glass, the price of hard glass is 4 times cheaper.
• Although not quite as scratch-resistant as Sapphire glass, the hard glass is also not easily scratched on impact. In particular, even if it is scratched, it can still be re-polished , and the glass still looks like brand new.
• Hard glass will have higher transparency than other types of glass. At the same time, with a refractive index of 1.47, hard glass will reflect less light and cause no glare when viewed.

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Other popular watch face materials

• Sapphire Glass: Made up of aluminum oxide (Al2O3) powder that undergoes the Verneul process to form Sapphire blocks. Sapphire glass’s hardness is on a scale of 9 on the Mohs scale (hard glass at 6.5 – 7 points on the same scale). There is only one stone in nature that is harder and can scratch Sapphire and that is diamond.
• Mica Glass (Acrylic): This is a cheap plastic glass, made from transparent Mica, often found in children’s watches.
• Mineral Glass (Mineral Crystal): Is a branch of tempered glass, adding inorganic mineral compounds. Essentially, mineral glass can be viewed as hard glass. However, mineral glass is more prone to cracking and breaking, and harder to polish than hard glass.

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Hopefully the above article has helped you better understand the concept and use of hard watch glass, and easily compare and choose for yourself the right watch glass material.