What Do You Say We Start a New Space Race?

Yeah, I'm being facetious.  

An interesting little story surfaced this week that seems to confirm an idea that has recurred in the science fiction world many times.  Imagine some material is discovered in space that is precious and in limited quantities on Earth but is practically free for the taking on some planet, asteroid, or somewhere else in space. All one has to do is get to the supply and take control over it - suddenly, riches beyond imagination. First one to the supply to get ownership of it is "winner takes all."

The story is based on data from NASA's Mercury MESSENGER probe, the first probe ever sent to orbit the small planet. Briefly, the roughly 1.1 metric ton satellite was launched on August 3, 2004, and went into orbit of Mercury just over 6-1/2 years later, March 11, 2011. It orbited Mercury until April 30, 2015. 

Analysis of the data leads to the conclusion that Mercury seems to have a 10 mile thick layer of diamond beneath the crust of the tiny planet. 

Astronomers have long noted that Mercury is different from other rocky planets they've observed, like Earth or Venus. Differences include its very dark surface, and remarkably dense core. Additionally Mercury's volcanic era seems to have ended fairly quickly in the planet's life. 

Another difference noted is that patches of graphite, a two-dimensional or sheet form of pure carbon, appear to be common on the surface of the planet. These patches have led scientists to suggest that in Mercury's early history, the tiny planet had a carbon-rich magma ocean. This ocean would have floated to the surface, creating graphite patches and the dark-shaded hue of Mercury's surface. 

"True color" image of Mercury taken by MESSENGER - using various filters on the spacecraft's wide angle camera to balance the reflected colors. Image credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie

The same process would have also led to the formation of a carbon-rich mantle beneath the surface. The team behind these findings thinks that this mantle isn't graphene, as previously suspected, but is composed of another much more precious allotrope of carbon: diamond. 

"We calculate that, given the new estimate of the pressure at the mantle-core boundary, and knowing that Mercury is a carbon-rich planet, the carbon-bearing mineral that would form at the interface between mantle and core is diamond and not graphite," team member Olivier Namur, an associate professor at KU Leuven, told Space.com. "Our study uses geophysical data collected by the NASA MESSENGER spacecraft."

Over the years, more than a couple of sci-fi stories have thought about an asteroid or planetoid that was considered insanely valuable; say solid gold or some unobtainium metal. In this case we're faced with a problem that has happened many times on Earth (although an extreme example): suddenly a prospector discovers a never before seen quantity of a valuable gem stone.  A pragmatic, practical answer to what happens in such a case is that price is really determined by "supply and demand" and if an unlimited supply were to suddenly appear, the price would collapse. It's not uncommon to try to keep such finds secret to keep from disturbing the price.

A gemstone is rather harder to SWAG a value on, compared to a pure metal. In the case of diamonds, there are well established standards - the "four Cs" based on the size of the stone (weight in carats - 5 carats to the gram) color and clarity of the stone along with how well it has been cut. While I could SWAG a calculation of how many kilograms of diamonds would be in a 10 mile thick shell the diameter of Mercury full of diamond crystals, think of thousands of cubic miles of diamonds, the real value would depend on things that would just be more cascaded "wild-ass guesses" and would essentially be meaningless. Bringing it to Earth would shift the supply so drastically that there would be no demand left once they got here.