Do ores, or at least cristalline materials, grow in the TES world? Br grow, I mean like vegetals, mushrooms or coral.

If so, then maybe the respawning of ore veins is lore-wise significant.

There is http://uesp.net/wiki/Lore:Lithnilian%27s_Research_Notesthat either meteoric glass or a magically altered version of it (namely Welkynd stones) could grow, and was indeed cultivated by Ayleids. If so, the Star Teeth and any other shard of Aetherial glass falling on Nirn could be seen as the spores or seeds of an unknown species. Also, according to some theories, the Sleeping Tree wasn't an Um-Hist but something which grew from a rock-seed thrown by the Red Mountain. In the depth of Blackreach, some aetherial mushrooms seem to grow on aetherium veins, or are maybe part of the aetherium itself, in case the vein is something like the mycelium of a mysterious fungus.

If they grow, what feeds their growth? Could this energy or nutrient be the reason why the Dwemer digged so deeply? Did they want to discover what lies at the root of ore veins? And how is the nutrient or energy conveyed through the "body" of minerals?

Another question that comes to my mind is : why is orichalc so important? Why did the Orc forgemasters choose to make from it their favourite material and why did a God (Diagna) choose to bring it to the Redguards? Why is there an Orichalc Tower?

Or more generally, each Tower seems to be related to some material. Orichalc, Brass, White Gold, Crystal, Diamond (The Direnni tower is Adamantine!)... I guess the Green-Sap is associated to a special wood (which is not so different from minerals if we admit the growing ores theory)... And We could see the Red Mountain as a Tower of Ebony, while the Snow Throat is maybe associated with snow that never melts, pretty much similar to Stalhrim. Why these materials and not other ones? What is so special about them? Why is there not, for example, a Mithril Tower? (Or at least, we don't know any such Tower...)

Finally, I have a question about Moonstone. Why is it named this way? Is it somehow linked to Lorkhan? But we http://uesp.net/wiki/Skyrim:Light_Armor_Forging in Skyrim that Moonstone was the key component of Altmeri weaponry. Why wold Mer forge anything out of a Lorkhanic material? And what interested the Thalmor in the forging of Stalhrim?

I hope that those aren't to far-fetched or fancy theories, but those are questions which were running in the background of my mind since a long time, and I thought they were worth asking.

About crystalline materials, I'm not an expert, but crystals actually grow in RL:

http://en.wikipedia.org/wiki/Crystal_growth

http://en.wikipedia.org/wiki/Crystallization

Now, ES being a metaphysical world, in which sunlight is actually magicka, I could imagine certain crystals and the mushrooms using magicka as a energy source and perhaps even nutrients. Aetherium crystals may form where the conditions are right for magicka to solidify itself into mineral composites.

I think that what dwemer wanted in the underground was to reach the Earth Bones themselves, the possible source of magicka for the crystals and mushrooms.

I figure it's just game mechanics to have veins respawn, the way I've seen mines work suggests that in-universe once you mine a vein dry you have to dig until you hit another one. Hence why a mine can be mined dry, and why they have to dig deeper and deeper over into the mine over time.

Indeed. Otherwise, you wouldn't have workers worrying about a mine running dry to begin with.

...unless the growth is much slower than the depletion...

Adamant/ine is simply a word that refers to the strongest material known to a society. For a long time that was diamond which is why it is sometimes used as a synonym for diamond.

Keep in mind that there is actual adamantium in Tamriel.

White-gold is only called that for its color. It's made from marble-like stone.