Diamonds: fifteen glittering facts

1. Diamonds were first mined in India 3000 to 6000 years ago.

2. The name “diamond” comes from a Greek word meaning “unbreakable.” Another word from the same root is “adamant,” meaning either incredibly hard or utterly unyielding in attitude or opinion.

3. Diamonds are a cubic crystal of pure carbon – the same material as coal or the “lead” (really graphite) in pencils.

4. Because diamond is made of carbon, combusting it with heat and oxygen leads to the production of carbon dioxide gas, as first demonstrated by chemist Antoine Lavoisier in 1772. Lavoisier used lenses to concentrate heat of the sun on a diamond surface until it began to vaporize.

5. Just one stray atom in a million can give a diamond a distinctive color. If the stray atoms are boron, the diamond will be bluish; if nitrogen, it will be a faint yellow.

6. In 2011, the recently discovered Cora sun-drop diamond, a 110-carat yellow pear-shaped diamond, sold at auction for $10.9 million.

7. Not only is diamond the hardest naturally occurring substance, it’s also the best thermal conductor. That is, it will transfer heat from one place to another much better than any metal.

8. Every year, 33,000 kilograms of diamonds are mined, while another 110,000 kilograms of diamond are manufactured synthetically. Only 20 percent of mined diamonds are large and pure enough to be gem grade.

9. Cutting a diamond to make a gem generally removes about half the weight of the diamond.

10. Most earthly diamond was created 1 to 3 billion years ago in the pressure and heat of the mantle around 100 miles under the earth’s crust. Diamond comes to the surface in volcanic events as magma rises through the crust.

11. Some diamonds are created on earth through impact from asteroids. When an asteroid strikes the earth, enough heat and pressure are produced to transform carbon in rocks into tiny micro- or nanodiamonds.

12. There are some stars in our galaxy, especially white dwarf stars, that have diamond at their core.

13 Although artificial diamonds can be manufactured under conditions of great heat and pressure, most industrial diamonds are now manufactured through a process called chemical vapor deposition. Very hot gaseous carbon compounds are allowed to gradually deposit ionized carbon atoms on a substrate.

14. While pure diamonds are excellent electrical insulators, diamonds with just a few atoms of nitrogen or boron can serve as semiconductors. There is great interest in developing diamonds as the next generation of computer microchips.

15. Russia just announced discovery of the largest geological diamond deposit ever found. The field of diamonds lies in a huge meteorite crater created 35 million years ago in Siberia. These diamonds are mixed with other forms of carbon, and one Russian scientist says they may be twice as hard as usual diamonds.


To learn more about diamonds, check out Mae and Clinton’s adventures in Pendred Noyce’s scientific mystery for kids, The Desperate Case of the Diamond Chip.

Be Sociable, Share!
Tags: , , , , , , , ,
Sep 19, 2012 | Posted by in Uncategorized | Comments Off