What Is Lonsdaleite? Is There Anything Harder than a Diamond?

Diamonds are the world's most coveted gemstone, with a long history tracing back as 6,000 years. Diamonds rank a 10, the highest possible ranking on Moh's Scale of Hardness. Diamonds are highly prized not only as gemstones but for use in industrial drills. It was widely believed by mankind to be the hardest substance on Earth. First, scientists have discovered how to manipulate molecules within certain substances that allow for a super compact atom arrangement, the result being a material harder than Diamonds. And then in 2009 scientists discovered that lonsdaleite, a naturally occurring mineral found in meteorites was harder than diamonds. It appears that diamonds have now relinquished its throne as Earth's hardest mineral.

Wurtzite in nature is not nearly as hard as diamonds. This is due to the impurities within the mineral. In order to become harder than diamonds, wurtzite boron nitride has to be synthesized in a laboratory. Wurtzite boron nitride is more stable in oxygen at higher temperatures than diamond. This makes it ideal to place on the tips of cutting and drilling tools operating at high temperatures, or as a protective cover on the surface of a space vehicle.

Ironically wurtzite boron nitride's hardness seems to come from the flexibility of the bonds between the atoms it is made out of. When the substance is put under pressure, the bonds bend by about 90º to relieve the tension. Although diamond reacts similarly, something about the structure of wurtzite boron nitride makes it nearly 80% stronger after the process takes place.

To quote the famous astronomer Carl Sagan, "the beauty of a living thing is not the atoms that go into it, but the way those atoms are put together." Well not exactly a living thing I am sure Carl would agree with me that the way atoms in lonsdaleite are put toghether is truly why this substance is so remarkable.

Lonsdaleite, diamonds, and for that matter, charcoal and graphite, are all composed of element carbon. But the structure of the Carbon atoms differs as lonsdaleite forms hexagonal patterns, earning the name hexagonal diamond. Scientists estimate that lonsdaleite is 58% stronger than diamond. Lonsdaleite is extremely rare and forms when meteorites of graphite hit the Earth's atmosphere and subjected to immense heat and pressure.

Diamonds Are Still More Pretty

Don't worry diamond lovers, diamonds are still more highly sought after for jewelry than boron nitride and lonsdaleite. Both wurtzite boron nitride and lonsadleite are extremely rare both in the lab and in nature. So it will be long time before diamonds are dethroned as Earth's favorite gemstone.

Marilyn Monroe once said, "Diamonds are a girls best friend." It seems that being the hardest known material in the world may help grind down titanium alloy, but does not necessarily make the one you love to say, "I do." Or maybe it will?