Posted on 07/03/2009 11:24:36 PM PDT by neverdem
The reputation of diamond as the hardest material around is under threat. Researchers in China and the United States recently determined that two naturally occurring substances surpass diamonds resistance to scratching and indentation. They calculated that the mineral lonsdaleitemade of carbon, like diamondis 58 percent harder than its famous cousin. And wurtzite boron nitride beats diamonds hardness by about 18 percent after being subjected to pressure, which alters its atomic bonds.
Still, in the short term diamond will continue to dominate in practical applications such as saws, drill bits, and industrial abrasives, since the newly studied materials are extremely rare. Lonsdaleite forms only under the extreme pressure and heat accompanying meteorite impacts, while wurtzite boron nitride is a by-product of intense volcanic eruption. But scientists can create both substances in the lab, says physicist John Janik at the Carnegie Institution for Science. Although producing the conditions required to grow the substances in bulk remains a challenge, Janik and others are working on synthesizing wurtzite boron nitride and lonsdaleite to pave the way for commercial use.
Wurtzite boron nitrides are a girl’s best friend?
Yes, but what of its refractive index? Diamond is generally considered to have the highest refractive index which is what makes it highly sought after (a merely semi-precious stone).
Cultured diamonds can now be grown from seed diamonds in the laboratory.
I wonder if losdaleite could be grown?
ping
lonsdaleite - When she likes it really hard.
If that's really a picture of it, it might be.
Swine flu pandemic 'caused by accidental leak from laboratory'
WHO warns swine flu 'unstoppable'
Carrots may help ward off cancer
Scientists Find Heart Stem Cells
FReepmail me if you want on or off my health and science ping list. Happy Fourth of July!
Really COOL article! It is always useful to discover primary things such as a “harder” substance!
Maybe in ten years, I’ll have drill bits and saw blades and maybe even sand paper that will last a little longer!
There are many other properties of diamond that these substances are not likely to duplicate, but the hardness can come in very handy in itself.
Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.