Are there any indications in any of [Tolkien's][1] works (stories, letters, notes, or anything) that suggest there can be elves of dark skin?

And the opposite: Is there any indication that there *cannot* be dark-skinned elves?

I'm interested in the race called Elves, the first born created by Illuvatar. But if there's another race that could be similar to elves, but dark skinned, that's a nice comment.

I am aware of the Moriquendi (Elves of Darkness), but as far as I know they received that name because they never gazed upon the light of the Trees, and the name is not at all related to their skin color.

For reference, I'm not familiar with British English from the first half of the previous century, so if some terms had a specific meaning back there and then I might have missed that meaning.

  [1]: https://en.wikipedia.org/wiki/J._R._R._Tolkien