Anything we can do, nature can do

[Image source: Discover magazine 80 beats blog]

The 80 beats blog of the Discover magazine reports another one of those scenarios where our illusion of one-upmanship has been shattered by nature.

In chunks of rock quarried from a Russian mountain range, physicists have found perfect “quasicrystals,” a type of material that researchers previously thought could only be created in a lab. [...] Quasicrystals were first created in the lab in 1984, and physicist Paul Steinhardt, a coauthor of the current study, says the hunt for naturally occurring quasicrystals began about 10 years ago. [...] One of those samples was a mineral called khatyrkite that contained tiny grains of an alloy made of aluminium, copper, and iron, and which was found in the Koryak Mountains in Siberia. As researchers explain in their study, published in Science, the khatyrkite’s diffraction patterns almost exactly matched those of synthetic quasicrystals made in the lab.

Scientists are yet to understand the natural forces and processes behind formation of these crystals. Understanding these processes will help in synthesis of new materials.

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• Exotic Quasicrystal May Represent New Type of Mineral (scientificamerican.com)

Harder than diamond

An article in New Scientist reports that two naturally found minerals that have turned out to be 18% and 58% harder than diamond. “The gemstone lost its title of the ‘world's hardest material’ to man-made nanomaterials some time ago. Now a rare natural substance looks likely to leave them all far behind – at 58% harder than diamond.”

The simulations of stress-response run by Zicheng Pan at Shanghai Jiao Tong University and colleagues showed that wurtzite boron nitride was 18% tougher than diamond under stress. The second, mineral lonsdaleite, is 58% harder. The first, wurtzite boron nitride has a similar structure to diamond but is chemically different. The second, the mineral lonsdaleite, is hexagonal diamond made from carbon atoms but they are arranged in a different shape.

“Paradoxically, wurtzite boron nitride's hardness appears to come from the flexibility of the bonds between the atoms that make it up. When the material is stressed some bonds re-orientate themselves by about 90º to relieve the tension. Although diamond undergoes a similar process, something about the structure of wurtzite boron nitride makes it nearly 80% stronger after the process takes place, says study co-author Changfeng Chen at the University of Nevada, Las Vegas, an ability diamond does not have.”

Cave of crystals: nature's wonder

Until you notice the orange-suited men clambering around, it's hard to grasp the extraordinary scale of this underground crystal forest. [Courtesy: MailOnline]

"Nearly 1,000ft below the Chihuahua Desert in Mexico, this cave was discovered by two brothers drilling in the Naica lead and silver mine. It is an eerie sight.

Up to 170 giant, luminous obelisks - the biggest is 37.4ft long and the equivalent height of six men - jut across the grotto like tangled pillars of light; and the damp rock of their walls is covered with yet more flawless clusters of blade-sharp crystal."

For more on this interesting story, follow the link.