earth's minerals

Jo Zebedee

Jo Zebedee

Aliens vs Belfast.
Supporter
Joined
Oct 5, 2011
Messages
19,401
Location
blah - flags. So many flags.
Are there any minerals which are more common on Earth than on other planets? I'd be particularly interested in any which could form part of a metal or, possible, an organic life form. Cheers!
 
How would anyone know? A couple of little robots wandering across mars? However, a wide selection of what we call minerals of biological origin - like marble (limestone), or coal, or amber - are unlikely to occur in an identical form anywhere in the galaxy.
 
chrispenycate said:
How would anyone know? A couple of little robots wandering across mars? However, a wide selection of what we call minerals of biological origin - like marble (limestone), or coal, or amber - are unlikely to occur in an identical form anywhere in the galaxy.
Click to expand...

Well if you don't know, I'm stuffed. :) back to socio-political thinking... Sigh.
 
Am I restricted to planets within the solar system? We might be able to find something that requires tectonic activity; I think the Earth's the only one that has that.

But if you state that haematite is unique to Earth (unlikely, but possible) who's going to be able to contradict you before about twenty or thirty years? Or pitchblende? Or crystalline quartz)

What sort of mineral would you like to be uniquely here? I'm sure I can come up with an argument why this should be the case as good as your average planetologist. It wouldn't be true, but nobody will find out until I'm well dead;).
 
If we're talking about minerals we're basically talking about metallic salts, in which case there are hydrous (includes water molecules in the crystals) and anhydrous (no water) crystals - but some specific minerals require the presence of water.

For example, Gypsum is hydrous Calcium Sulphate - CaS04 - and also includes 2 x H20 in the chemical formula. Meaning that gypsum must form in the presence of water. This is a point of note because a few years ago one of the Mars rovers identified a rock formation as containing gypsum, proving that standing water once existed on Mars.
 
My chemistry knowledge is rubbish, but I do remember reading that carbon is the base of all our life because it has a capacity for bonding with other atoms, enabling complex molecules to be built up. Silicon (I think) could theoretically do the same.

Not sure whether I read that in a bio-textbook or in Bang! The Complete History of the Universe.
 
Haematite requires an oxidising environment; I seem to remember reading that the reason for thick seams of this mineral all over the world is that the oceans changed from generally reducing to generally slightly oxidising when photosynthetic life first evolved. This meant that the most common iron species in the water changed from being Fe2+ to Fe3+ and the most stable Fe3+ compound is iron (III) oxide (Fe2O3) otherwise known as... haematite.

Limestone is not unique to life-bearing planets, but fossiliferous limestone is. So, IIRC, is chalk - which is basically an accumulation of miniature seashells.
 
I had thought that all limestone was basically compressed chalk, ie bivalve skeletons (and all marble was the result of further compression) Certainly jurassic limestone (from the Jura, the big lump that runs from Geneva to Basle) is. How else, apart from the evaporation of shellfish-inhabited seas/lakes can it be concentrated like that?

Yes, Thaddeus, carbon is convenient for complex molecules. Other tetravalent's might also function, but carbon is common in the universe, and it's always convenient to start your industrial processes with something you've got a lot of.

One of the problems with using silicon is the CO2 analog is silica – sand. Not easy to breath out, and doesn't tend to dissolve in much, so you've got an automatic additional complexity before you even start generating energy cyles.

And water exists on lots of planets/moons. Admittedly frequently as a solid, but hydrogen is the most abundant element in the universe, and oxygen's on the main chain fusion sequence. Trouble is it's a lightweight molecule and… just a minute, I was boring everybody with this stuff over in the low gravity thread.
 
I had heard silicon touted as a possible alternative building block of life to carbon too. I think it was Masters of Orion, one of the races was a silicon base dlife form that could live in extreme environments but that reproduced and evolved very slowly.
 
One of the problems with silicon as a life basis is that it doesn't form chains in the same way carbon does; silicon-silicon bonds are quite weak.

It's conceivable that with just the right balance of elements, silicone chains in which the silicon atoms are separated by oxygens might form spontaneously. These compounds are quite stable; in fact, they are more stable than carbon-carbon chains.

The problem with SiO2 being a solid could be solved in one of two ways. First, solid waste products aren't an insuperable problem; quite a lot of bacteria photosynthesise H2S in water solution leaving solid sulfur behind. Secondly, the core reactions of respiration could be reductions instead of oxidations, using hydrogen; SiH4 is gaseous.
 
springs if you are looking for an outside life form why do you need the most abundant?

most rare metal source are of meteor origin. or come from deep volcanic activity

what is curious is the lack of trace minerals here that are abundant elsewhere. someone once gave a very good argument for cyanide as something breathable by other races instead of oxygen.

we didn't have oxygen at first. the oxygen is almost a waste package of garbage polluting our atmosphere. what was there was methane... nitrogen.. helium and others.. we give off methane as a waste product.. what if that was what the aliens needed?
 
The heavier the atom, the rarer the metal, so very heavy metals like titanium or uranium are rare - on Earth, and everywhere else in the Universe. - See more at: Metals - Chemistry for Kids!
Click to expand...

I assume you are looking for a reason for an alien race to invade Earth?

There is another item in abundance on Earth and not elsewhere (that we know of) - Humans!
 
Just please don't make whatever you select too cheesy... Anyone whose read the lost fleet probably squirmed when a whole interstellar treaty was established based on duct tape
 
ralphkern said:
Just please don't make whatever you select too cheesy... Anyone whose read the lost fleet probably squirmed when a whole interstellar treaty was established based on duct tape
Click to expand...

I'll try my best to avoid duct tape. :D i have cheese-alert people advising me well. :) my brain seems to be sorting out some sort of order.
 
Most uninhabited planets with no tectonic activity are primarily comprised of igneous (volcanic) rocks, which as far as I know tend to be of the basaltic (thin, hot, runny flows - think Hawai'i) kind, meaning mafic rock-forming minerals such as magnesium, calcium and iron dominated pyroxenes, olivines etc are predominant. As has been said, oil and bitumens (inc coal) as well as "gemstones" such as jet, opal, and amber don't exist without life forms. Diamonds and corundum gems (sapphire and ruby) don't exist without the metamorphic forces provided by continental collisions and ejecta of deep crustal melts such a kimberlites. As such they don't exist without plate tectonics. You get the picture haha.

Hope that helps even if I'm waaay late on this . :)
 
You must log in or register to reply here.
Thread starter Similar threads Forum Replies Date
A Living underground believing earth's atmosphere is unbreathable Book Search 8
M New method of archaeological dating based on Earth's fluctuating magnetic field and events involving a big fire Science & Nature 5
T (Found) Becoming Earth's greatest enemy to motivate them to win a war Book Search 7
Robert Zwilling Earth's Crystallized Iron Content in Solid Core Growing Lopsided Science & Nature 9
M End of Neanderthals linked to flip of Earth's magnetic poles, study suggests Science & Nature 4

Similar threads


Back
Top