No, on every count. Firstly: no coal. Coal is the fossils of trees, primarily of the Carboniferous period. Life is required for coal, and active geological processes. Secondly: Pressure is a force exerted inwards, toward the centre of a planet, due to the weight of all the mass above it. Geological processes do force material to the surface, and a diamond planet will likely have none anyway. Diamonds of any size are not known for their internal activity.

Ever wonder...if humanity needed diamond so much that they'd sacrifice everything to get it?

Think they'd ever harvest Sol? (Sol being the sun)

Just a thought... would humanity go to such extremes?

If we had the technology readily available, certainly.

So we'd be set to take away the thing that gives us life?

Hah...seems humanity's ignorance would be placed before our way of life.

Given that Sol is not the right type of star to contain carbon... no, they wouldn't.

If it was, then it would depend why they needed it. If it was a choice between destroying the sun and attempting to use technology to live with out it, or certain death by not coming up with a diamond... of course they would.

Isn't Sol's core made of diamond?

According to wikipedia, less than 0.3% of the mass of the sun is Carbon. And most of the nuclear reactions in the core are hydrogen-based.

I can find nothing about sol containing diamond, either.

Supposing it did, if we had another planet that depended on another sun and no rational need for the ol' girl anymore I can see no reason why we wouldn't.

Hah, really?

Shit, I mind reading somewhere, for the life of me I cannot mind which star (if one or more) had a diamond core.

Further research is required.

I've read somewhere that stars can. I'd assume that they would need to be those carbon star things.

EDIT: It seems that it's possible for white dwarfs to crystallise.

Brown dwarves can crystallize because they are so cold or something. I found out yesterday the coldest star in the known universe (a brown dwarf) has a surface temperature of just 350 degrees C

I'm disappointed that I can't think of a Warhammer joke to put in there.

What could we possibly need with so much diamond? The cost of acquiring any of it would be greater than the value of it, you'd either not get enough, and if you got all of it, it's still worthless because it is a mass greater than that of the Earth that can't be sold or stored or anything. I know we pretend to exchange gold everyday while leaving it where it is, but no one has attempted to trade with diamond stars hundreds of lightyears away, for good reason.

Also, if you did get any of it, the value of diamond would plummet like nothing in history, it would be worth less than dirt (mainly because we'd have significantly more diamond than dirt, but also because dirt is actually useful). I know the diamond industry would quash any industrious expedition to the diamond planet, if none of the other reasons were somehow good enough.

The only value in diamond stars and planets is scientific illumination, which is worth more than diamonds anyway.

it would be nice to make a ship with a stasis field,you enter fly into space,set course,go to stasis,wake up at the planet,take a chunk of diamond and return to earth,and become a millionare.

I'll throw you into Jupiter's gravity well.

• DIAMONDS FOR THE FABULOUS GOD
• In the grim diamondness of the far future, there is only... ore.
• I hear Space Marines can cut diamonds just by looking at them funny.
• So I bought my girlfriend a diamond Necrolace.

This is hard.

The fourth one was a real gem.

If there are any people left to sell it to after a millions years of space travel, and if there is still a worthwhile economy amenable to such an endeavour, and if diamonds are still worth anything, and if diamonds are still worth anything after you arrive to flood the market with them.

yeah,but the only exctiting thing would it be that you managed to go to another star and walk on it :)

i got a joke for diamonds,chuck norris can cut diamonds with his mind

Diamonds normally are.

*Badump-tisch*

Our sun will start to fuse Helium into Carbon in its red giant phase, about five billion years from now.

can't wait!

We can give up squeaky voices and balloons, for a really really easy way to get gems.

DO WANT!

Now I need a time machine.

At that time the Earth will have either drifted into a wider orbit due to the sun's loss of mass, and be a charred cinder, or else have been swallowed up along with Mercury and Venus as the outermost reaches extend beyond the Earth's orbit. The red giant phase will last only a few million years before, unable to fuse Carbon, the sun's outer layers puff away and the white dwarf core is left to slowly cool.

Betelgeuse's death will be cooler, and quite possibly within our own lifetime. Or rather, witnessed in our own lifetime, it would have died centuries ago.

out of solar sails and anti matter engines what is most likely to happen

Either either or neither.

Anti-matter has the same problem as the universal solvent, and solar sails can only take you in one direction.

Just like real sails!

Real sails can take you in any direction within a 270 degree arc, the 90 degrees you can't go being centred on the direction of the wind. This means you can sail upwind in a zig-zag fashion.

This is possible because of the water, a medium which prevents significant downwind drift because of the shape of the ship's hull: moving forward, the pointy end, is simply the path of least resistance. In space there is no second medium to drive through, so the only direction to go is with the force of the solar wind.

This is also why airships with sails could only go in the direction of the wind, like a hot air balloon. I was devastated when I worked that truth out, I tell you. So many rich plans...

what is universal solvent? a one way trip with solar sails could still be used to send probes to the near by stars, and when you get to a near by star the solar wind would be changed and they could head back, although I here they plan to use lasers as a booster so coming back would take a lot longer, and the overall trip would be too long to actually send a person.