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ArcticMyst Security by Avery

Diamonds are forever






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You know diamonds are not forever at all, they are actually undergoing a spontaneous chemical reaction that is turning them into carbon! lol

... notice the word "spontaneous" and not "instantaneous," two completely different meanings...
 

Benm

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You know diamonds are not forever at all, they are actually undergoing a spontaneous chemical reaction that is turning them into carbon! lol

... notice the word "spontaneous" and not "instantaneous," two completely different meanings...

Its not even a chemical reaction since its just a change from one allotrope to the other. At room temperature the kinetics are such that diamonds are forever in the sense that they will last longer than our sun will - thats sort of my criterium for calling things 'forever' in this perspective.

Once you get higher temperatures it process will speed up turning them into graphite, but if its done in the atmosphere, they'll just burn up. This doesnt require extreme conditions either, diamonds have been known to burn up in house fires where people recover a little puddle of gold from the ring they were in, but no sign of the gem.
 

Benm

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Well, something like silicon carbide might be. Its nowadays produced in gemstone quality and very much like diamond (even higher refractive index, almost as hard), and its fire resistant - at least to temperatures seen in house fires. When cut properly no lay person is likely to tell the difference, apart from the fact that these things can be produced more or less to arbitrary size.

In any case, diamond will lose its value over the coming decades. Synthetic technology keeps on advancing, and i'm quite sure will see a larger lab grown diamond of gem quality than nature ever managed to surface.

In that sense, gold is more 'forever' than diamons are, since its abundance is known to be low, and sythesis will remain very expensive.
 

Trevor

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graphite is forever!

I'd say subatomic particles are forever... but not really. Quarks are forever?

Or rather, according to e=mc², energy is forever, because matter and energy are the same... :whistle:

Trevor
 

Trevor

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neither of which can be created or destroyed.

Well... energy is energy and matter is energy. We have a way to turn matter into pure energy - so we can't really call them two discrete substances (for lack of a better term), just two forms of energy. Water is still water, even when frozen.

I just consider everything energy, thus the first law of thermodynamics is always true.

Trevor
 
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Yep, everything that exists, is energy. When we feel that substance we call matter in our hands, such as a stone, it is really the repelling effects of the outer electron shells of the atoms in the stone against the outer electron shells of our fingertips. A complex energy interaction, that also allows the eyes to see the material, as photons fly from its surface and into our retinas. We know that "matter" is there, but in some ways it's an illusion created by energy. The stone is "real" enough however to put a lethal dent in our craniums LOL.
 
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Actually it's known since about 150 years that diamonds upon burning up produce a bit more energy than the equal weight of coal, due to the energy stored in their tighter bonds. Also at that time, a diamond was converted to carbon by focusing sunlight on it, with the diamond in vacuum under glass so it wouldn't burn; thus proving its composition.

For the pricing, gem-quality diamonds are a fully controlled market (De Beers mostly), so there actually is no real market at all - the prices are arbitrary. Thus diamonds are very risky as an investment. Diamonds are very useful in industrial applications (for drills and saws and so on), but these are today mostly synthetic (the rest is cheap waste from gemcutting, or low-quality natural diamonds). As Benm wrote, nowadays even carat-sized synthetic diamonds are possible.
 
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