Subscription Center
Feb 19, 2009 | 1
In addition to being the traditional token of marital intent, the diamond has long provided the—ahem—gold standard for super-hard materials. But physicists at Shanghai Jiao Tong University and at the University of Nevada, Las Vegas, say that two lesser-known materials, wurtzite boron nitride and lonsdaleite, are even harder.
Wurtzite boron nitride, the researchers calculate, resists indentation with 18 percent more fortitude than its glittering counterpart, whereas lonsdaleite, a hexagonal lattice of carbon atoms also known as hexagonal diamond, boasts indentation strength a whopping 58 percent greater than that of diamond. That would be a new record for hardness, the team claims in the study, published this month in the journal Physical Review Letters.
See what we're tweeting about
notscientific Charles Darwin's exquisite description of fireflies http://t.co/TCSNjFMeiS #scilogs
sciam Summer Blockbuster: A Black Hole Swallows a Cloud http://t.co/rwjptA4zwd
MRAKdesign Speaking of #cicadas: ah so cute. http://t.co/H4DP1J2eSk
Deadline: Jun 29 2013
Reward: $7,000 USD
The Seeker for this Challenge desires proposals for chemical methods that could rapidly degrade a dilute aqueous solution
Deadline: Jul 30 2013
Reward: $100,000 USD
The Seeker desires a method for producing pseudoephedrine products in such a way that it will be extremely difficult for clandestine che
Powered By: 
YES! Send me a free issue of Scientific American with no obligation to continue the subscription. If I like it, I will be billed for the one-year subscription.
