The Earth Story

Hands up if you’d like a diamond for a few dollars? The Crater of Diamonds located in Arkansas, USA allows you to be the miner and search for diamonds, and then keep any you find. The Crater of Diamonds was first discovered by J. Huddlestone in 1906 who spotted odd crystals in his soil. Since then 30,000 diamonds have been found in the park by some of the 3,000,000 visitors each year. With prices of $10 for adults and $6 for children aged 6-12, it's a fun family day out!

Diamond marbles I first saw these on a trip to Antwerp many moons ago, made from what would once have been industrial quality rough, full of inclusions. Only about 40% of the crystal remains once sculpted into a sphere, so using cheap starting material is important, particularly since they have not been easy to market in jewellery. They would certainly survive the kind of brutal plays that were essential back in my playground marble playing days than the glass ones I has, that always ended up being slowly chipped to pieces. Loz Image credit: Gorenstein diamonds http://www.worldlargestdiamonds.com/news/the-metallic-look-the-revolution/

Howard Tracy Hall

Some of you may remember this legend from a story told in the hit series Breaking Bad.

Known simply as Tracy Hall by colleagues, friends and family, he was the first person to successfully create synthetic diamonds in a lab. In return for this ground breaking invention, the company for whom he worked, General Electric, rewarded Hall by giving him a $10 savings bond.

While at GE, Hall constructed a pressure chamber. He called this chamber the half-belt. This chamber was designed to be used to create high pressures in a rundown Watson-Stillman press.

When Hall requested funds from GE to build a superior pressure chamber, he was turned down. Eventually, through persuasion and multiple favours, he managed to build his pressure chamber.

On 16 December 1954, in an empty lab, Hall finally tested his process with his new equipment. Upon checking the results of his experiment he said, "My hands began to tremble; my heart beat rapidly; my knees weakened and no longer gave support. My eyes had caught the flashing light from dozens of tiny . . . crystals."

On this day, Hall became the first person to make artificial diamonds. After several tests confirming Hall’s results, GE announced to the world that they had created artificial diamonds, but the press release didn't mention Hall.

Unrecognized, Hall eventually left GE and began working at Brigham Young University. Hall went on to invent a better apparatus to create synthetic diamonds, the tetrahedral press. With this new invention, he and two friends founded a new company, MegaDiamond.

GE made millions from Hall's invention as synthetic diamonds are widely used in electronics, optics and cutting tools.

by Renesh T

Image source:

http://bit.ly/1LdqxUu

References and further reading:

http://bit.ly/1BjVlb3 http://bit.ly/1BjVw6j http://bit.ly/1ApPUs2 http://lat.ms/1ApPYYy

The diamond rock Professor Larry Taylor at the University of Tennessee literally has tens of thousands of diamonds in his office. Of course, before you break into the department to go after those diamonds, you should realize that they’re not the gem-quality stones found at jewelry stores. Instead, many are tiny and not worth much. In fact, the reason Dr. Taylor gets his hands on so many is that the mines really don’t want them. This rock comes from the Udachnaya mine in Russia, a giant hole dug in the ground at the site of a kimberlite. Kimberlites are volcanic eruptions that carry material from deep in the mantle, including diamonds. The mine pulls gem-quality diamonds out of the ground, but in addition it gets rocks like this with tiny diamonds. Since this rock doesn’t have gem-quality diamonds, the mine happily passed it to Dr. Taylor, whose research group tore into it to see what secrets about the mantle it could unlock. Dr. Taylor’s group has developed a technique using X-rays to take a 3-D, internal picture of a rock. X-rays pass through a rock and interact with the different minerals, allowing imaging of the grain shapes without breaking it apart. Using that technique, they found that this little rock contained a whopping 30,000 diamonds. Their results were presented last week at the 2014 American Geophysical Union meeting (#AGU14).  The diamonds are tiny but they tell a lot about how the rock formed. Some of the diamonds contain even smaller inclusions of the garnet and pyroxene minerals that make up the bulk of the rock, showing that the diamonds grew after the other minerals were already present.  The diamonds also sit in specific layers within the rock and contain inclusions of carbonate minerals. Carbonates are the same substance many species at Earth’s surface use to make their shells, so finding those minerals in the mantle is really interesting. On top of that, the chemistry of these diamonds also seems to reflect processes that happen at the Earth’s surface. The processes through which diamonds form in the mantle are still not well known – carbon must make it to great pressures and crystallize into diamond, but why it happens in some areas and not others isn’t known.  Finding carbonates and specific flow paths inside this rock implies that the source of these diamonds probably has something to do with subduction – the carbon that went into these diamonds originally sat on the floor of the ocean and was dragged into the mantle at a subduction zone. This may not be the only way that diamonds form, but evidence from Dr. Taylor’s research is making a strong case that it’s at last one of the major ways it happens. -JBB Image credit: Larry Taylor http://www.livescience.com/49154-diamond-rich-rock-russia.html https://agu.confex.com/agu/fm14/meetingapp.cgi#Paper/30237 Read more: http://www.smithsonianmag.com/ist/?next=%2Fscience-nature%2Fdiamonds-unearthed-141629226%2F