Toughing it out.
Step aside diamonds, there's a tougher material in town. Using computer simulations, researchers have found two minerals that beat diamond as nature's hardest substance: wurtzite boron nitride and lonsdaleite.
Like diamonds, these materials are crystalline solids (solids whose atoms, or smallest unit of an element, are arranged in a regular repeating pattern). When wurtzite boron nitride and lonsdaleite are compressed, the bonds between atoms malting up the minerals' crystals change their orientation. This transforms the minerals into superhard structures, allowing them to withstand greater pressures than diamonds can.
The only drawback to these materials is that they are rare in nature: wurtzite boron nitride is formed in volcanoes, and lonsdaleite is the result of meteorites crashing into Earth. So, diamonds may reign supreme a while longer.
STRENGTH OF WORLD'S HARDEST MATERIALS
Scientists measure a material's hardness in gigapascals, a unit of pressure (force applied over an area), How much stronger is lonsdaleite than wurtzite boron nitride? Than diamond?
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|Title Annotation:||GRAPH IT/MINERALS; on wurtzite boron nitride and lonsdaleite|
|Article Type:||Brief article|
|Date:||May 11, 2009|
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