Africa is home to the world’s largest diamonds - but advances in mining technology are enabling other regions of the world to get in on the act. Most recently, Canada unearthed the biggest diamond ever found in North America - the Foxfire. It has spent the last couple of months on display at the Smithsonian’s National Museum of Natural History in Washington.
Self-study activity:
Watch the video and answer the questions below about it.
1. When did the story of the Foxfire diamond begin?
2. Why do we know the Foxfire diamond was bigger at some stage?
3. When was the Foxfire discovered?
4. How much did Deepak Sheth pay for the diamond?
5. What will happen to the Diavik mine in a few years’ time?
The story of the Foxfire diamond began two billion years ago, when it was forged by fire and forces deep beneath the Earth. Now the largest uncut diamond from North America is being studied by scientists at the National Museum of Natural History.
It looks like a lump of quartz.
I think a lot of people would agree with you and I'm sure a lot of people, if they saw that just laying along the side of the road, would probably not even think about picking it up.
Diamonds are as mysterious as meteorites. Both travel through time and space to offer clues about the origins of the universe. These diamonds perilous journey is even more remarkable as most are destroyed or splintered by the volcanic action that propels them at high speed to the Earth's surface.
We know by looking at these flat surfaces that there was more to this diamond at one time, that during either this violent descent as part of this volcanic eruption, or the explosion at the surface, or the mining operation, something caused this diamond to be broken and these flat faces are the broken cleavage surfaces, so someplace, someplace there are other pieces to this diamond.
Better get hunting.
Better get looking. We don't know this is the biggest piece or the smallest piece. Somewhere there are other pieces that would fit on to these flat surfaces right here.
The Foxfire was discovered in 2015 in one of the most inaccessible parts of the world, the Diavik mine in the barren lands of Canada's Northwest Territories, about 130 miles from the Arctic Circle.
The mine spends most of the year frozen in snow. Last year the Foxfire was sold at an auction to Deepak Sheth, a businessman and collector.
So can I hold it?
Of course, of course, please. You’re holding a history.
Holding history that's very heavy.
Yes, it is hundred and eighty-seven point sixty-three carat diamond. It's a miracle of nature.
How much did you pay for it?
Many, many millions of dollars.
How many millions?
I'm sorry. [I] cannot divulge that.
But it's worth many, many millions, it’s a multi-million dollar diamond.
Yes, it is.
I'm feeling quite nervous you can take it back.
Sure, sure.
Mr Sheth plans to keep the diamond in its rough condition but anyone hoping to find its missing parts had better hurry. In just a few years the Diavik mine will close, leaving any treasure buried beneath the ice.
Jane O'Brien, BBC News Washington.
Key:
1 two billion years ago
2 by looking at its flat surfaces
3 in 2015
4 he won’t say, many millions
5 it will close