New mineral discovered inside deep-Earth diamond now named after Alberta geochemist

From the coalfields of northern England to the arctic zone snows and the steamy jungles of federative republic of brazil, adamant huntsman and scholar Graham Pearson has carved a name for himself that now lives on in rock.

A newly-discovered mineral has been named after Pearson — an honour approved by the International Mineralogical Association late last year.

It's called Grahampearsonite and it was found in Brazil, inside a deep-Earth diamond.

Pearson, a mantle geochemist with the University of Alberta in Edmonton, has spent decades in mantle geology and mineralogy. He's considered a world-leading expert on diamonds and what they tell us about the Earth's interior.

His lifetime of research on diamonds has included his work in Brazil where he and his team made discoveries over a decade ago that helped explain, through deep-mine diamonds, the composition and water content of the Earth's deep mantle.

"The most lasting legacy of our work as scientists is really the data we produce but those ideas get modified," Pearson said in a recent interview.

"So if you are lucky enough to have a mineral named after you, that's not going to change.

"[And] we're going to run out of new minerals soon. So it's very humbling to think that one of those minerals found is named after me."

Grahampearsonite was discovered inside a diamond that crystallized at depths greater than 300 kilometres below the Earth's surface in Brazil's Juina region.

According to a research paper detailing its discovery, the mineral's chemical formula is calcium, phosphorus and oxygen.

Grahampearsonite was first known as a synthetic material and can be found in products such as toothpaste abrasive.

Known as calcium pyrophosphate, scientists already knew how to create the material in a lab but this was the first time it has been found occurring naturally.

Using X-rays, researchers looked through the diamond while the mineral was still trapped inside, revealing its distinct crystal structure.

The international research group named the prism-like mineral after Pearson, to honour his "outstanding contributions" on diamond research.

It got its official name in December.

"It might be arcane, but it's really beautiful," he said, as he points at a diagram of Grahampearsonite, which is made out of calcium and diphosphorus. The diagram shows oxygen flowing between the chemicals.

"Only natural-occurring minerals can be named [after a person]," Pearson said.

And someone has to discover it, put it in a huge amount of work to characterize it, justify its namesake and then get it approved by the International Mineralogical Association.

"The association decides whether what [researchers have] done is good enough and solid enough to warrant the name of a new mineral," Pearson said.

Pearson is a trailblazer in diamond research.

In addition to mapping the history of the Earth's mantle, Pearson has developed new techniques for geochemical analysis and pioneered methods for dating minute geological samples.

Born in the United Kingdom, he was brought up in an English mining town called Pontefract. "I've been surrounded by the products of mining," he said.

And similar to the formation of diamonds, he said his love for the mineral was also a slow burn. His PhD adviser, who was researching a rare graphite mineral from Morocco that used to be a diamond, piqued his interest.

"That got me into the world of diamonds and studying the deep Earth," he said.

In 2010, he moved to Canada to work for the University of Alberta. He established the world-class Arctic Resources Geochemistry Laboratory.

He continues to research minerals and diamonds in the Arctic.

Pearson said ongoing mineral discovery is important.

"It's hard to predict what applications some of these synthetic minerals have until you discover them," he said.

"And I'm a natural scientist and something made synthetically just does not hold the same allure. All the story it tells is that someone put these elements together in a lab and cooked them."

He said most people like the appearance of diamonds because they sparkle, but said there's a lot more to them.

"It's capable of trapping residual pressures inside it that no other mineral is capable of doing," he said. "That's what gives it the ability to retain these pieces of the deep Earth. Those elements are also able to tell us amazing things about plate tectonic cycles."

Pearson said advancement in microscope technology has also made it easier to identify new minerals and humanity will eventually discover all the minerals Earth has to offer.

We're about halfway there.

"About 4,800 minerals have been discovered," he said.

"There's about another 4,000 probably waiting to be discovered."

Fakiha Baig is a journalist with the Canadian Press.

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