[Galadriel]

I'm completely with Nerwen and Morthoron.

Plus, I don't think Tolkien was the type to leave things like that. If the Arkenstone truly were a Silmaril, then it would have played some bigger part than being taken out of the earth, only to be put back again. I'm pretty sure it would have popped up somewhere else (like the Ring did).

And, well, I just don't think Dwarves (or anyone else) could have actually cut the Silmaril. Also, the fact that it actually lay by a dead Dwarf...it just doesn't fit. If a Silmaril had to be anywhere, it would either be in Valinor or in the depths of the earth, unfound. I think that's where it belongs. *sigh* Don't take me seriously. I'm rattling nonsense.

However, after reading this:

"Arkenstone is a modernization of an ancient word which appears in the Edda as jarknasteinn and in Old English as eorclanstán.

Note that Tolkien used the word eorclanstánas to refer to the Silmarilli in Old English texts by Eriol"

I'm not so sure. Tolkien played with words like little boys play with knives...