A root in The Etymologies of the 1930s, first glossed “copper” and then “metal”, with derivatives ᴹQ. rauta/N. rhaud “metal” and serving mainly to explain names like N. Angrod and N. Finrod (Ety/RAUTĀ). It might have reappeared in the name S. Rodëol “metal of Eöl” from later Silmarillion drafts (WJ/322), but by 1957 Tolkien was explaining the final element of S. Finrod as S. raud “noble” (PE17/49, 118), so I think it is likely that ᴹ√RAUTA “metal” was abandoned.
Neo-Eldarin: For purposes of Neo-Eldarin, I’d use Q. tinco (LotR/1122) and its cognate [N.] tinc (Ety/TINKŌ) for “metal” words. For “copper” I'd use derivatives of √(U)RUS (VT41/10).
A root in The Etymologies of the 1930s glossed “valiant”, its most notable derivative is the name S. Beren “Bold”. It had a variety of derivatives having to do with daring, such as ᴹQ. verya-/N. bertha- “to dare” and ᴹQ. verya/N. beren “bold”. The continued appearance of the name Beren in the later versions of The Silmarillion implies the root remained valid, but this name was only translated in The Etymologies of the 1930s, so it could have shifted in meaning.