Sapphire screens just one step down from diamond-hard (pictures)

Displays made from the second-hardest compound on Earth would be extremely hard to scratch or break. CNET checks out a sapphire screen prototype.

Jessica Dolcourt

Feb. 28, 2013 4:33 a.m. PT

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Sapphire screens: Almost diamond-hard

BARCELONA, Spain--Want a truly unbreakable cell phone screen? Lab-grown sapphire could be the screen of the future. In this demo unit we saw at Mobile World Congress, a sapphire cover screen is glued on top of the phone's glass screen. Despite the double layers of material, the phone was still just as responsive.

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A rock and a hard place

I hit and dragged a piece of craggy concrete repeatedly against the screen.

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Scratch attack

What happened? Nothing. There wasn't a crack, scratch, or sign of any pitting, just a tiny amount of concrete fairy dust that wipes away with your thumb.

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Compared to Gorilla Glass

The thin wafer of reinforced Gorilla Glass (right) wasn't as lucky. Although the chemically strengthened Gorilla Glass wards off cracks, glass isn't indestructible.

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Sapphire's many forms

Chinese company Zhejiang Shangcheng Science and Technology shaped both the smartphone screen (left) and the jewel with sapphire supplied by GT Advanced Technologies.

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Screens and things

Zhejiang Shangcheng Science and Technology showed off a range of possible forms and applications at Mobile World Congress 2013.

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No joke

It took 16 days to grow this 250-pound block of sapphire. From here, the boule, as it's called, can be shaved, shaped, polished, and sliced into fine wafers.