[Galadriel55]

I think the fact that Elves are portrayed as "constantly elegant" does not mean that they are squeamish or contemptuous of dirty work, but rather that the work for them is not dirty at all. They are just creative beings, and they turn everything into creation, into art. Arranging food on platters is an art, not a service. Mining is also an art, and a rather skill-demanding one. And good metalwork (and I therefore presume good metal extraction from the ground) is a skill that's honoured, so perhaps it's not as lowly as you make it sound.

I realize that I'm talking more about late Third Age ME Elves when I talk about art. The First Age Elves were darker, certainly had less smooth "class systems" and more tensions between them. However, I still think that their essence of creativity rather than destruction is present throughout.

And this brings me to the main point of how Elf mines could have been different from Dwarf (or orc) mines. Unlike those two, Elves don't seem to make industries for anything. They don't make more things for the sake of making more; they make just as much as they need for the foreseeable future. They use wood too, but they would never chop down forests; the Dwarves, while they have intentions of creation, can lose track of the destructive aspect - which is why they awoke Durin's Bane, and why Yavanna was concerned about their existence. When Dwarves make, they make it an industry. Elves don't; if they had mines, those mines would be smaller and as harmless as possible. Those Elves who lived underground probably had more extensive mines, but still not "industry scale" like the Dwarves, and certainly not "full on destructive" like the orcs. So I think they had some mines, but they were smaller and not used as often.