Friday, August 05, 2005

Diamonds are... [Addendum]

Great! I can see the bottom of my blog pile!

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.
(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.



Caesura said...

Wow Diamonds abound! That was a fun post. My Birthstons is the Opal. I looked up something about the opal birthstone:

"Opal Birthstone charaictalistics - Hope: Today, one ounce of fine Opal is worth about ten times the price of one ounce of gold. It is said in mythology, the learned men in times of Helen of Troy expounded on the virtues of the Opal, claiming it possessed the most beauty of all gemstones known to them. It was described by Shakespeare as the "miracle and Queen of gems", possessing magical qualities. It's fiery beauty makes the Genuine Opal one of the most popular gemstones of modern times.

Genuine Opals are mined in the Lightening Ridge area of Australia, an extremely arid climate."

And here is a link to some opal photos :)

JP said...

Funny, I was just reminded that my birhtstone is sapphire, which I really like, although opals are cool too. I also think diamonds are overrated because the price is artificially inlated by Debeers, and not all diamonds are a billion years old, they can make them in laboratories. But they are a really cool substance, and purty. I don't know what sapphires are made from, probably shit and sulphur, but they have a nice color.

How can colored diamonds only have one element? What gives them color?

Man, that is DENSE. (Diamonds, that is.)

The Talking Mute said...

I was born on April 7th and it's always a delight when people give me my birthstone as a gift. Diamonds are indeed a girl's best friend. :)

The Talking Mute said...

Hi Olivia,

I noticed that your sidebar is out place. Mad Perseid, a fellow blogger, posted an instruction on how to fix it as indicated below:

You need to adjust the “width” setting of the #sidebar in your template. The numbers shown here are from my blog, yours will be different. Increase the width until you get sidebar to display properly.

#main {
background:#245 url("") no-repeat right top;
#main2 {
padding:15px 20px;
#sidebar {
background:#cdb url("") no-repeat left top;

Olivia said...

Caesura -
Oooh, I used to wish opals my own birthstone except that in gem mythology there is a sadness of some sort attached to them.
However, I could stare at them for ages looking for the little scintillations, specially in the fire opal. Thanks for the link.

Olivia said...

JP -
Sapphire, eh? Isn't that quite a hard stone?
ANYWAY, I was studiously avoiding acknowledging the existence of laboratory diamonds *hmph!*

Coloured diamonds still consist of Carbon, but are contaminated with different gases. No arguing that it's more than one element - surely the atomic structure of the diamond remains the same!

Olivia said...

Talking Mute -
Well hello fellow April-baby! Aren't we special?

I haven't noticed that my sidebar is out of place. Thanks for the code, which I've kept in case it does happen (again?) - let me know next time if it's still crooked.

OJ said...

Actually Diamonds are the hardest substance known to mankind as well!

JP said...

if a N atom replaces a C atom in the lattice, is it simply filling a gap in the structure, trapped spatially without chemical bonding? I guess so, otherwise the molecular structure would be altered, and it would no longer be diamond. Man, the wonders of science! Why can't science and religion get along, they'll both blow your mind.

Anonymous said...

quite fascinating.
science and religion could get along IF we let them.

Kim Plaintive said...

Interesting post! (Found your blog via the "Next Blog" button.) My birthstone is emerald -- it's hard to find an emerald that isn't full of dark carbon spots or white spots though (without spending a ton of money).

Alter Ego said...

That was such an interesting post, Olivia! Thank you. (Alohalani)

Me said...

quite interesting.....but oj said that
"Actually Diamonds are the hardest substance known to mankind as well!"
but its not true....tungsten carbide is the hardest substance...which is also used for cutting diamonds.....
anyways first time here....nice post...

Olivia said...

JP - well there you go, you figured it out.

Vanessa - yes, like at UST ;)

Kim Plaintive - Welcome! Wow, emeralds seem such a serious gem to have, don't they?

Alohalani - you're quite welcome ;)

Wanderer - welcome to you too! ...Which is why I added "naturally-occurring", which Tungsten carbide is not.