Sapphire glass vs Corning Gorilla DX glass

The Sapphire and Corning Glass DX glass are used in making the display screen of smartwatches and smartphones. We look at the key differences between the Sapphire Glass and the Corning Gorilla DX glass below.

Content in this post:

  1. Salient points
  2. Hardness
  3. Display
  4. Breakage
  5. Environmental impact
  6. Costs
  7. Weight
  8. Commercial production
  9. Summary

Salient points

  • Sapphire is a naturally occurring mineral. It is considered the second hardest mineral after diamond.
  • Sapphire glass is actually a thin sheet made of sapphire crystal. It is not made of glass. It is called Sapphire glass as it has the appearance of glass. Technically speaking, the Sapphire crystal is melted to create the sheet for the watch screen or smartphone screen.
  • Both, the Sapphire glass and Corning Gorilla DX glass are used to make the display screens of smartwatches and smartphones.


Sapphire glass is much harder than the Gorilla Glass DX. The most common points about the hardness of the Sapphire glass are mentioned below:

The sapphire glass is very hard to scratch. It is practically impossible to scratch it unless you make a strong impact on the watch screen. Your watch will do fine without a scratch guard sticker.

Sapphire glass has a Mohs rating of 9. This is next to the diamond’s Mohs rating of 10. Effectively speaking, this would mean that the smartwatch made of sapphire glass will scratch when it comes in contact with the harder material of diamond. Mohs is a standard used to measure the hardness of minerals. It rates minerals on a scale of 1-10 for hardness with 10 being the hardest mineral.


The Sapphire glass reflects more light and is dimmer than the Corning Gorilla glasses. In terms of reading indoors, a smartwatch made of the Sapphire crystal will pose some difficulty due to a duller screen. On a similar basis, if you do a lot of trail runs in forests, you may want to check visibility issues on a sapphire crystal watch screen. You will have difficulty reading the watch screen without a backlight. Poor light on the watch for reading is a challenge for the Sapphire glass watches.


There are no two ways about the fact that the Sapphire glass is harder than the Corning Gorilla DX glass. But, in terms of breakage susceptibility, we find that the Sapphire crystal glass has a greater risk of being shattered.

Sapphire glass has a higher tendency to break. If it breaks, it actually shatters into small pieces. Any strong impact on the sapphire glass display could cause the display screen to shatter completely. This is one of the negative points of a Sapphire crystal glass. The propensity to break is higher for sapphire glass.

Environmental impact

One of the significant downsides to using a Sapphire watch is the impact on the environment. It requires a high amount of energy as part of the manufacturing process. Sapphire crystal is heated to over 2000 degrees Celsius temperature for melting it and making a Sapphire sheet.

Therefore, the environmental cost of making sapphire glass is quite high. For people looking at environmental costs, a Gorilla Glass DX would be a more ideal fit. As part of the manufacturing process, the Gorilla glass would need to be heated to temperatures of 400 degrees Celsius. This is significantly lower heating than the Sapphire crystal glass.

Sapphire glass is not a mass-market product. Due to the intricacies involved in producing Sapphire glass, it cannot be produced at mass levels. However, the Corning Glass DX and other Gorilla glasses can be commercially produced at mass levels.


Due to the nature of the production process and the time needed to make Sapphire crystal glass, the overall cost of Sapphire crystal glass is high. Compared to the Gorilla Glass, the Sapphire glass sheet could be costlier by 8 to 10 times. For price-sensitive smartwatches and smartphones, the Sapphire glass would increase the costs of the device by a significant rate.

Corning Gorilla Glass DX has an anti-reflective coating. This ensures that the glass has better brightness and enhanced readability. It is much better to read a watch screen of Gorilla DX glass than a Sapphire glass. Due to the improved readability of the Corning Gorilla Glass DX, the battery life of the smartwatch will also improve.


Sapphire glass is much heavier than the Gorilla Glass DX. In common terms, a Gorilla Glass DX weighs one-third of the Sapphire glass. For lean and thin watches, it makes all the more sense to use a Gorilla Glass DX on the lens of the watch.

This is also the precise reason that the Garmin Fenix watches with Sapphire glass are broader and heavier than the ones made of Corning Gorilla DX glass material.

Commercial production

Gorilla DX is only manufactured by Corning. When it comes to manufacturing Sapphire glass, there are multiple established companies that can make the Sapphire glass. Some of these are Kyocera and GT Advanced Technologies. There are more companies that make Sapphire crystal glass.


Corning Gorilla DX is a commercially viable glass material for smartwatches. The Sapphire crystal glass lends a premium feel to the watch. But the cost and environmental impact of manufacturing the Sapphire Glass is higher than that of making Gorilla Glass.

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Rajesh Dhawan

Rajesh Dhawan is a technology professional who loves to blog about smart wearables, Cloud computing and Microsoft technologies. He loves to break complex problems into manageable chunks of meaningful information.