Back in 1971, a meteorite fell to the Earth and landed in Finland. Since that time, the rock has been poked and prodded but it didn’t reveal its secrets until recently, when scientists began polishing the rock with a diamond-based paste. Their exploratory analysis soon revealed two entirely new forms of carbon, essentially diamonds that are significantly harder than anything on Earth.

But what apparently happened in the Havero meteorite is that graphite layers were shocked and heated enough to create bonds between the layers — which is exactly how humans manufacture diamonds, Chen explained.

Ferroir’s team took the next step and put the diamond-resistant crystals under the scrutiny of some very rigorous mineralogical analyzing instruments to learn how its atoms are lined up. That allowed them to confirm that they had, indeed, found a new “phase” or polymorph of crystalline carbon as well as a type of diamond that had been predicted to exist decades ago, but had never been found in nature until now.

“The new structure is very interesting,” Chen told Discovery News. “It gives us some clues so we can try to make it in the laboratory, and then investigate it.”

Among the things that would be interesting to learn, Chen said, is how hard are the new kinds of diamonds. The sample from the meteorite was far too small to test for hardness, except to show that it is certainly harder than regular diamonds.

“The only evidence we have for a higher hardness than diamond is the fact that we polished the rock section with a diamond paste and that our polymorph and polytypes were not polished by this material,” said Ferroir. “This why we do think that its hardness is harder than diamond.”

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