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How Gorilla Glass Works


The Fusion Draw
A dip in a special salt bath is what gives Gorilla Glass its damage-resistant properties.
A dip in a special salt bath is what gives Gorilla Glass its damage-resistant properties.

While you might think of glass in its manufactured form, the truth is it's a material we find in nature. Certain rocks and minerals become glass after coming into contact with high temperatures. This occurs naturally along lava flows and places where lightning has hit the ground.

Humans have been creating glass for millennia. Furnaces capable of generating incredible heat melt the right type of rocks down into what we call a glass melt. At this stage, you can shape the glass in many ways, including using a tube to push air into the mass. We call this technique glass blowing.

Commercial glass tends to come from three main sources. The first is sand, which we refer to chemically as silicon dioxide. That's the type of material Corning uses in its manufacturing process. The other two types of materials in commercial glass include limestone and sodium carbonate.

Corning takes the silicon dioxide (SiO2) and combines it with other chemicals before melting it down into a glass melt. The resulting glass is aluminosilicate -- that means the glass contains aluminum, silicon and oxygen. The glass also contains sodium (Na) ions, which become important in the next phase of manufacturing.

Corning pours the molten glass into a V-shaped trough but doesn't stop at filling the trough to the top. The company continues to add molten glass until the glass begins to overflow the sides of the trough. Automated robotic arms draw the sheets of glass from the edge of the trough. Each sheet is just over half a millimeter thick.

If you were to use this glass for a screen on your electronic devices, you'd end up with a very clear covering. But it's not damage-resistant like Gorilla Glass -- it's just aluminosilicate glass. To give Gorilla Glass its ability to withstand scratches and cracks, Corning gives these sheets of glass a little bath.


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