This Gold Nugget Is Lighter Than Latte Foam
Wednesday, November 25, 2015 - 16:00
in Physics & Chemistry
Gold foam resting on top of milk foam Gustav Nyström and Raffaele Mezzenga / ETH Zurich via press release Researchers at the ETH in Zurich have made the lightest gold foam ever. 98 percent of it is made from protein fibers derived from milk (just 2 percent is gold). And even though it looks like pure gold, it’s light enough to float on top of a cappuccino, according to a press release. Solid foams like these are made when the liquid in a gel is replaced with air. The structure is overall left the same, which leaves the resulting material mechanically strong but without any weight from water. Depending on what the fibers in the foam are made of, it could even be biocompatible or biodegradable. To make the lightweight gold foam, the...