Apple Watch's Sapphire Crystal Display Evaluated With Diamond Tester
YouTube channel Unbox Therapy has shared a new video that tests the stainless steel Apple Watch with a basic diamond tester to determine if it actually has a sapphire crystal display like many regular mechanical watches. The video also tests the Apple Watch Sport, LG G Watch R, iPhone 6 and a Tissot watch that is verified to have a sapphire crystal display.

The results of the test confirm that the Apple Watch does have a sapphire crystal display as advertised, with the diamond tester recognizing the thermal conductivity of the scratch-resistant material. The verified Tissot watch also displays a reading on the meter, while the Apple Watch Sport, LG G Watch R and iPhone 6 do not yield any results because all three devices have traditional or ion-strengthened glass displays.
Sapphire crystal is a harder and more scratch resistant material than traditional glass, which is why Apple chose it for the more expensive Apple Watch and Apple Watch Edition display and lenses of the heart rate sensor. Apple cut the sapphire crystal with a diamond-encrusted wire to allow for a precise fit and polished it with diamond-covered pellets for a smooth and glossy finish.
"Sapphire is the second-hardest transparent substance after diamond," reads the Apple Watch materials page. "That’s why we chose it to cover the Apple Watch and Apple Watch Edition faces, and to make the lenses of the heart rate sensor. Our sapphire crystal comes from the highest-quality boules. Only the purest, clearest, and strongest sapphire crystal is harvested. To ensure a precise fit for the case, the crystal is cut using a diamond-encrusted wire. To make room for an integrated antenna, a tiny groove is laser-ablated around its perimeter. And to create the smoothest possible finish, the crystal is polished with diamond-covered pellets."
Apple Watch has been put through a variety of tests since it was released last week, giving users an idea of how the wrist-worn device manages based on both normal and unrealistic usage. CNET shared an Apple Watch torture test on Friday that, among other things, involved submerging the watch in hot water and pouring ketchup and maple syrup on it, while another video took the Apple Watch into the shower and swimming pool as part of a waterproof test.
Popular Stories
Apple provided developers with the third beta of an upcoming iOS 26.2 update, and there are still new features that are being added with each beta that we get. We've rounded up all of the changes that Apple made in beta 3.
AirDrop
Apple added new AirDrop functionality, providing a way for two people to share files temporarily without having to add one another as contacts.
iOS 26.2...
Apple is preparing for Tim Cook to step down as CEO of the company "as soon as next year," according to the Financial Times.
The company's board of directors and senior executives "recently intensified preparations for Cook to hand over the reins," the report said.
While the report said that Apple is unlikely to name a new CEO before its next earnings report in late January, it went on to ...
Apple today announced an expansion of AppleCare+ coverage in India, with new options for monthly and annual plans, and the addition of Theft and Loss for iPhone for the first time.
Options for monthly and annual AppleCare+ plans in India provide more choice and flexibility, allowing users to keep coverage for as long as they require. Apple's vice president of Worldwide iPhone Product...
Apple today released new firmware designed for the AirPods Pro 3, the AirPods 4, and the prior-generation AirPods Pro 2. The AirPods Pro 3 firmware is 8B25, while the AirPods Pro 2 and AirPods 4 firmware is 8B21, all up from the prior 8A358 firmware released in October.
There's no word on what's include in the updated firmware, but the AirPods Pro 2, AirPods 4 with ANC, and AirPods Pro 3...
We're officially in the month of Black Friday, which will take place on Friday, November 28 in 2025. As always, this will be the best time of the year to shop for great deals, including popular Apple products like AirPods, iPad, Apple Watch, and more. In this article, the majority of the discounts will be found on Amazon.
Note: MacRumors is an affiliate partner with some of these vendors. When ...
In select U.S. states, residents can add their driver's license or state ID to the Wallet app on the iPhone and Apple Watch, providing a convenient and contactless way to display proof of identity or age at select airports and businesses, and in select apps.
Starting this Wednesday, November 19, the feature will be available to residents of Illinois.
The announcement confirmed that the...
Apple recently teamed up with Japanese fashion brand ISSEY MIYAKE to create the iPhone Pocket, a limited-edition knitted accessory designed to carry an iPhone.
iPhone Pocket is available to order on Apple's online store starting today, in the United States, France, China, Italy, Japan, Singapore, South Korea, and the United Kingdom. However, it is already completely sold out in the United...
Most of Apple's Macs are slated to get M5 chips across 2026, and there's a possibility we'll even see the first M6 chips toward the end of the year. Updates are planned for everything from the MacBook Air to the Mac Studio.
MacBook Air (Early 2026)
The MacBook Air will be one of the first Macs to get a 2026 refresh, with an update planned for the first few months of the year. The MacBook...
In his Power On newsletter today, Bloomberg's Mark Gurman reiterated that Tesla plans to add Apple CarPlay support to its vehicles "in the coming months."
This is easily the biggest news for the regular version of CarPlay in years, should Tesla actually follow through with offering the system in its vehicles.
As noted by Gurman, this would be a stunning reversal for Tesla and its CEO Elon ...
Starting with the upcoming tvOS 26.2 update, currently in beta, additional profiles created on the Apple TV no longer require their own Apple Account.
In the Settings app on the Apple TV, under Profiles and Accounts, anyone can create a new profile by simply entering a name and indicating whether the profile is for a kid. The profile will be associated with the primary user's Apple Account,...