Washington, Dec 28 : Scientists have come up with the world’s first unscratchable 18-karat gold that is harder than steel and can be used in jewellery, watches and other high end products.

Gold is a beautiful and popular precious metal but it is also soft and vulnerable to scratches. Therefore other metals are needed to make it more resilient however that brings down its quality.

Now, a research team from the EPFL in Switzerland, with support from Swiss watchmaker Hublot, have created a very hard high-quality gold. And recently, they unveiled the shiny result, the Discovery News reported.

“What is radically new is being able to make something that is both extremely hard and 18-karat gold. The challenge was to stick with that boundary,” said Andreas Mortensen, a metallurgy professor at the EPFL in Switzerland who led the work.

Others have been able to create hard gold in the past but they have not been successful in achieving the level of hardness required to meet the 18-karat standard, separating real gold from impure gold.

The EPFL team used boron carbide, a ceramic that is one of the hardest materials in the world, along with diamonds to make the new gold. This material has myriad applications, including as a component in bulletproof vests.

Initially the ceramic was heated in an oven to more than 3,600 degrees Fahrenheit, producing a three-dimensional network almost like a scaffold, with just the right amount of pores.

That network was then infiltrated with liquid gold, implying that the scientists pushed gold into the pores. Eventually, the combination was solidified to form the composite material.

According to Mortensen, the new gold looks and feels distinctive. It is harder to the touch than other gold, and has a darker hue. The material is so hard that no coating is needed to make it unscratchable. Even though that is an advantage to watch-wearers looking for durability, there is a trade-off as it is to some extent more fragile than pure gold that is soft.

“What Professor Mortensen and his group have done is to come up with a very nice material that has a combination of the luster of gold but it has the strength of other metals that are much stronger,” Nikhilesh Chawla, a professor of materials science, engineering, and mechanical engineering at Arizona State University who specializes in metal composites said.

“The composite material really tries to give you the best of both worlds,” Chawla added. (ANI)