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The launch of the iPhone 6 and 6 Plus are just days away, and a lot of the talk about the new devices are their larger, ion-strengthened glass screens.

Now the American Chemical Society has created a video that explains why this type of screen is typically stronger than other displays - and it involves using a hot bath of potassium. 

The video also reveals many of the other elements found in smartphones, including gold, silver, tin, and even arsenic.

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The American Chemical Society has explained how the ion-strengthened glass on the iPhone 6 and 6 Plus (pictured left to right) is stronger than regular glass, because it is placed into a hot potassium bath. The chemist has also revealed other elements found in phones such as silver, gold, tin, aluminium and silicon

In the build up to Apple's iPhone 6 event, nearly every report claimed the devices would have a sapphire screen.

Instead, Apple unveiled 4.7-inch and 5.5-inch handsets that both feature ion-strengthened glass, during last week's launch.

According to the American Chemical Society's video, created with help from experts at the Compound Interest blog, ion-strengthened glass is created using a potassium bath.

One method is to dip the glass into a hot bath of potassium salt, typically potassium nitrate, at around 300°C (572°F).

This causes the sodium ions in the glass to migrate, which in turn causes sodium ions in the glass surface to be replaced by potassium ions from the bath solution.

The larger potassium ions in the bath squeeze themselves into the holes created by the moving sodium.

This compresses the glass, to accommodate the larger ions, which in turn makes it stronger.

When broken, chemically strengthened glass still shatters, similar to traditional glass, but it is said to be between six and eight times stronger.

An alternative method for strengthening glass, is submerging the glass into a sodium nitrate bath first.

This enriches the surface with more sodium ions, and when the ions in the glass are immersed in potassium nitrate, there are more sodium ions to be replaced, which increases the compression and strength.

By comparison, sapphire screens are made from synthetic sapphire - a hard, transparent material made of crystallising aluminium oxide, produced at high temperatures.

Ever wondered what exactly goes into an iPhone?

To make ion-strengthened glass, glass is placed into a hot bath of potassium salt, typically potassium nitrate, which is around 300°C (572°F). This heat causes the sodium ions in the glass to migrate, which in turn causes sodium ions in the glass surface to be replaced by potassium ions from the bath solution (illustrated)

By comparison, the Apple Watch (pictured) features a sapphire crystal screen

As the material is heated, it forms disks that can be sliced using diamond-coated saws.

These round disks are ground into shape, and polished, to become glass.

The technology is traditionally used in watch displays because it is thin, super-strong and scratch resistant.

Apple already uses sapphire crystal in the Touch ID fingerprint scanner on its latest iPhone 5S and to protects the phone's camera.

Elsewhere, the screen on typical smartphones are also made up of extremely rare elements called praseodymium, gadolinium and terbium.

And to achieve the charge needed to power the touchscreen, a compound of indium, tin and oxygen is used in a transparent film that conducts electricity.

The video also explains that a typical smartphone contains about 300 milligrams of silver and 30 milligrams of gold, housed in an aluminium case.

Copper is used in the wiring and circuitry, and the silicon chips that power the devices also feature oxygen, antimony, phosphorous, gallium and arsenic..

'So there you have it. Those are the elements that make up the phone, you can't put down,' concluded the American Chemical Society.

Elsewhere, smartphone screens are also made up of extremely rare elements called praseodymium, gadolinium and terbium. And to achieve the charge needed to power the touchscreen, a compound of indium, tin and oxygen is used in a transparent film that conducts electricity

The video also explains that a typical smartphone contains about 300 milligrams of silver and 30 milligrams of gold, housed in aluminium. Copper is used in the wiring and circuitry, and the silicon chips that power the devices also feature oxygen, antimony, phosphorous, gallium and arsenic (pictured)