Smashing $7000 diamonds, melting them in a nuclear reactor and the search for the untapped mother load -- welcome to the sexy, sci-fi side of geology.
At the University of Melbourne this month, geologist David Phillips picked up a diamond and a hammer and set to work destroying it. Did anyone protest?
“Yes, just about all the ladies in the school,” Phillips told The Huffington Post Australia.
He said diamonds may be hard, but “a few lusty blows with a hammer usually sorts them out”.
He destroyed this particular $7000 diamond to find clues about to how it made it through the Earth’s mantle and crust.
Hint: it involves a volcano.
“All natural diamonds, like the ones you find in jewellery, have been brought up by volcanoes many tens of millions of years ago,” Phillips said.
“Diamonds grow like any other mineral about 120-200kms below the earth’s surface, and when a volcano rises up, it picks up the diamonds along the way.
“As magma comes up from the bottom, it has to break its way up to the surface and it basically rips up fragments of surrounding mantle rock, which is where you find the diamonds.”
Diamond mines usually straddle long-dead volcanoes but sometimes, diamonds are found in rivers or on shore lines, and the old volcano they’ve come from -- presumably full of diamonds -- is yet to be discovered.
Instead of an Indiana Jones-style search through the jungle, Phillips said clues to the diamond mother load were entombed inside diamonds -- clues that are slightly radioactive.
“What I’m looking for is an extremely rare diamond with a slightly green flaw,” Phillips said.
“You might find one in 10,000 diamonds.”
The green fleck is evidence of a rare mineral -- that’s radioactive.
Yep, radioactive, green diamonds.
By ageing the radioactive component, Phillips can determine the time said diamond shot out of a volcano, and this narrows down the search for the volcano.
The sci-fi diamond story isn’t over yet; it’s not enough to smash these diamonds apart -- the fragments containing the green flaw then need to be melted in a nuclear reactor.
“We use a research reactor at Oregon State University where they melt the inclusions with a laser and analyse them on a mass spectrometer.”
So, it ti worth destroying one diamond to lead you to the location of the mother load?
We say yes.