A new test shows that the iPhone 6 sapphire display panel may not be entirely scratch-proof as originally suggested by previous tests.
Videos putting the 4.7-inch iPhone 6 display panel to the test emerged earlier this month, with the screen put up against rocks, knives, keys and other sharp objects just to see how much punishment it could take.
It survived those tests with little more than a scuff to its name, but now it seems the panel isn't as resilient as originally thought.
Notorious tech vlogger, Marques Brownlee, managed to get his hands on a supposedly real 4.7-inch iPhone 6 panel, but this time tested it with different types of sandpaper.
He tests the sandpaper and the sapphire display using the Mohs scale to try and guage how much sapphire the panel actually contains.
The Mohs scale is used to categorize the hardness of minerals, with diamond at the top and talc somewhere near the bottom, for example.
Gorilla Glass, used in the majority of high-end smartphones including iPhone 5S, rates as 6.8 on the Mohs scale, but sapphire is the second hardest, naturally occurring mineral and ranks 9.0.
First, Brownlee tests the sapphire panel with a garnett sandpaper, which ranks about 7.0 on the Mohs scale, meaning it should be able to scratch up Gorilla Glass but not the sapphire display.
It's instantly noticeable that the sapphire panel is able to be scratched with the garnett sandpaper, meaning the panel isn't 100 per cent sapphire. The Touch ID home button on the iPhone 5S for example, did resist scratches from the garnett, so has a higher percentage of sapphire than the iPhone 6 display.
Secondly, Brownlee tests the panels with emery sandpaper, which sits around the 8.0 mark on the Mohs scale.
The sapphire display holds up a lot better than the Gorilla Glass of the iPhone 5S, but there is definite scratches on the iPhone 6 screen. This means that although the sapphire panel is a lot more resilient than the Gorilla Glass, it's not indestructible or completely scratch proof.
Brownlee’s friend then shoots it with a crossbow arrow, just because they can. Obviously it shattered though.
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