Great! I can see the bottom of my blog pile!
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Last month, Moonglow asked a question about birthstones and I've been meaning to blog it ever since.
Being an April baby, my birthstone is diamond, a fate which I reluctantly accepted because I thought them overrated.
THEN a few years ago I learned some really cool things about diamonds, such as:
1. They are the only gem composed of one element (Carbon)
2. All diamonds are at least one billion years old, most about 3bln
3. They are so dense that they slow light to half its usual speed (of 186,000 mph)
4. They are so dense that they remain cooler than the ambient temparature
5. Their facets disperse all the colours of the rainbow
Number 3 and 4 really got my attention, and I became sort of awed by diamonds.
Then I won the DeBeers lariat that you all know about by now and took it as a good omen.
Last year I went to a Cartier exhibition at the Houston Museum of Natural History and finally fell in love with number 5 because my eyes were
dazzled.
At the Soane museum on Tuesday I asked Delightful what he would collect if he had to be a collector, and *without hesitation* he chose coloured diamonds...which, as with many things he mentions, was so unusual that I had to let it sink in.
The same evening on the way home, I spotted a Tube poster for the upcoming diamond exhibition at the NHM. *anticipation*
...a girl's best friend.
...forever.
(pick your ending)
**********
Addendum -
After some of your comments I've done a little research.
Caesura - Opal is a hydrous Silica with metal oxides. Sort of loses its romance after that.
OJ - Indeed, diamonds are the hardest
naturally-occurring substance known to man. (10 on the Moh scale)
The word "diamond" comes from the Greek
adamas meaning "untameable".
JP - Sapphire is the next hardest gem (9 Moh) after diamond. It is composed of Aluminium oxide coloured by iron and titanium.
Coloured diamonds are extremely rare and occur through gas contamination, the most common being Nitrogen (yellow). A N atom would replace a C atom on the crystal lattice.
Boron-contaminated blue diamonds are used as semiconducting material, but if the blue is caused by Hydrogen, they are not.
Colour can be added in a lab with pressurisation. Might as well just wear a topaz...
Diamonds unfit for gemstone use are known as bort and prized for their hardness and conductivity, rather than brilliance.
Oh, and one last thing before I forget...
No I forgot...
Ohhh and it was interesting too.
OH I KNOW. Precious stones are classified as being above 7 or 8 on the Moh scale; semiprecious as below.
FIN