Okay, maybe I'm an idiot, but this is one of those facts I'd missed until recently. Despite the impression you may have gotten from grade school and/or old Superman cartoons, diamonds are probably not lumps of coal that just got compressed real good—at least, not in exactly the way you might imagine.
Diamonds are made out of carbon, but the best evidence suggests that they form far more deeply down in the Earth than coal does. Instead of coal being smushed into diamonds, imagine something more like those "grow crystals out of Borax and water" experiments you did in grade school. Only, in this case, the experiment is performed in the fiery depths of Hell, as very un-coal-like atoms of carbon are compressed and heated deep in the Earth's mantle until they start to bond together and grow into a crystalline structure.
Once the crystals are formed, they get to the surface of the Earth via volcanic eruptions.
The really interesting thing about all of this is that it's one of those ideas that's very hard to verify. Diamonds form at a depth we can't go observe directly. All we have to work with is indirect evidence. Because of that, nobody knows exactly where the necessary carbon to make diamonds comes from. This is why the "diamonds are coal" story exists. Some scientists think the carbon is stuff that's existed in the Earth since this planet was formed. Others think it might be coming from terrestrial carbon that got shifted down to the lower levels via plate subduction—although, even then, we're talking about carbon, but not necessarily coal. It could be a combination of both. Either way, the mental image of smushed coal doesn't quite work.
Read the American Museum of Natural History's explanation of where diamonds come from
Read an interview about diamonds with the curator of the U.S. National Gem and Mineral Collection
Thanks to a story written by Geology.com's Hobart King for busting the myth and inspiring to me to read a little more on this
Image: Diamonds, a Creative Commons Attribution (2.0) image from kimberlyeternal's photostream
In 1960, parapsychologist Anthony Donald Cornell donned a bed sheet and attempted to scare an audience watching an X-rated film in a movie theater. Why? Cornell, a believer in ghosts himself, wanted to understand how people reacted during “apparitional experiences.” Today at the BBC, University of Oxford experimental psychologist Matthew Tompkins explores Cornell’s strange experiments […]
With so many costumes adorning this election season, you might think the Halloween get-ups are overkill. Think again, because David Ng and B.R. Cohen are here to present the official universal survey about your candy favorites for the 2016 hierarchical delineation of candy virtue.
University of Zurich researchers used transcranial magnetic stimulation, a noninvasive method of inhibiting activity in parts of the brain, to “turn off” people’s ability to control their impulses. They focused on the temporoparietal junction, an area of the brain thought to play an important role in moral decisions, empathy, and other social interactions. They hope […]
I’ve never really felt the need to purchase a smartwatch because a lot of them aren’t very functional, but at just shy of $30, the Martian Notifier Smartwatch was worth checking out. For that low of a price, it actually does feature an impressive amount of functionality, and comes in handy when you don’t want to be carrying around your […]
Geek Fuel is a subscription delivery service that caters to those of us that love comics, gaming, and general geek culture. Every month, Geek Fuel will assemble a box of goodies with a value of $50 or over. The specific items are a mystery, but you’ll always get an exclusive t-shirt not found anywhere else, a full […]
If you like to DIY and you like helicopters, you’re going to really love the Flexbot Hexacopter Kit. This copter blows traditional models out of the water: it includes everything you need to actually build your own hexacopter, and then pilot it like a pro, too.The construction is complicated enough to give you a challenge, […]