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.

applewatchunboxtherapy
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.

Related Roundup: Apple Watch 10
Buyer's Guide: Apple Watch (Caution)

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Top Rated Comments

OllyW Avatar
133 months ago
I don't think there was ever any doubt about Apple using real sapphire crystal displays. :confused:
Score: 61 Votes (Like | Disagree)
arubinst Avatar
133 months ago
So... was anyone expecting a different outcome?

It's not like Apple is going to sell something else and label it as sapphire :rolleyes:
Score: 28 Votes (Like | Disagree)
Patriot24 Avatar
133 months ago
I think the Unbox Therapy guy is nice and knows his stuff, but my god does he take forever to get to the point in all of his videos. This one in particular could've been 30 seconds.

"Oh look, it really is Sapphire." ROLL CREDITS.
Score: 27 Votes (Like | Disagree)
kdarling Avatar
133 months ago
I don't think there was ever any doubt about Apple using real sapphire crystal displays. :confused:
No kidding! :rolleyes:

How about testing something that we don't know yet. Like:

- What's the battery size in the 42mm????

- How long does a watch go if you put it into Reserve Mode at 100% battery?

- Is there a way to fool the wrist detection and move the watch to another arm?

- Heck, what if you just put a piece of white tape (or a band-aid) under the watch? Does this allow the owner to wear it looser?

- I.e. Is the detection looking for a pulse? And if so, is that only every ten minutes?


- etc
Score: 13 Votes (Like | Disagree)
DavidTheExpert Avatar
133 months ago
I would have gone with the stainless steel model for the sapphire display if only there were more color options. I went with sport because I liked the space gray color better. The space black stainless steel was nice, but it only comes with the link bracelet putting the minimum price at a thousand dollars. Eff that.
Score: 13 Votes (Like | Disagree)
realeric Avatar
133 months ago
Don't feed the troll(=Unbox Therapy).
Score: 11 Votes (Like | Disagree)