Have you ever imagined, what can be as precious as gold; but as light as air? Well, I don’t know about the past, but in today’s time, its gold only! Yes, you read it right. Few scientists from ETH Zurich were able to convert gold in the form of a foam, which can be easily molded by hands. With this discovery, gold foam has become the lightest metal on earth, ever discovered.
Gold foam? How does it look like?
Researchers say that though gold foam is as light as air, it’s difficult to tell the difference between solid gold and gold foam by naked eye. It so happens because of the aerogel that boasts the metallic luster. This amazing discovery has made the gold foam so soft that it can be molded by hand. That’s possible because the gold foam consists of 98% air and only 2% of solid gold metal. Of this solid metal, over four-fifths are gold, and less than one-fifth is milk protein fibrils. This corresponds to around 20 carat gold, according to the researchers at ETH Zurich (Swiss Federal Institute of Technology). All in all, gold foam consists of a three-dimensional mesh of gold of mostly pores.
That’s why the lead of this research, Raffaele Mezzenga who is a professor of Food and Soft Materials calls the gold foam as a material that is “lighter than water and almost as light as air”.
How the gold foam was created?
The scientists created this the gold foam by heating milk proteins to produce nanometer-fine protein fibers, that are also called as amyloid fibrils. These fibrils were later placed in a solution of gold salt. The protein fibers interlaced to form a basic structure, along which the gold simultaneously crystallized into tiny particles. This resulted in a gel-like gold fiber network.
Gustav Nyström, the first author of the corresponding study in the journal Advanced Materials mentions,
“One of the big challenges was how to dry this fine network without destroying it,”
Where can we use the gold foam?
Scientists mention that the material holds unique properties. It is a metal, but due to its porous structure, it is also light. As a result, it can be successfully used in jewelry and watches. Besides, it can be used as a revolutionary catalyst since it has huge surface, with very little quantity. It can be used in chemical labs across the world to carry out several chemical tests on this precious metal.
Gold is not the first metal to be converted into a foam. Scientists have successfully converted copper also into a foam earlier. The copper foam is used in various researches and tests in chemical labs.