Celebrimbor doesn't actually appear in JRR
Tolkien's
Quenta Silmarillion. Christopher Tolkien edited him in,
based on a note from JRRT [see the contents of
the note below].
Christopher Tolkien's addition, published in the1977 Silmarillion:
"In that time Celebrimbor son of Curufin repudiated the deeds of his father, and remained in Nargothrond; yet Huan followed still the horse of Celegorm his master."
Maybe I should add that, in the discarded conception wherein Celebrimbor was a Jewel Smith of
Gondolin, he was a Noldorin craftsman, not a Feanorean -- so, for examples of changing ideas, we have him as a Noldorin artificer in Gondolin -- then a Feanorean (
published by JRRT in the 1960s for the Second Edition) -- then a Teler in
Aman (late text) -- or a Sinda who claimed descent from Daeron (another late text)!
In any case, as Tolkien himself published Celebrimbor as a descendant of
Feanor, and as Lord of Eregion (Appendix B, and so on, in
The Lord of the Rings), I take this as the actual history.
. . . although yes
(it appears) Tolkien forgot (or something), or in any case, in a later text made him a Telerin
Elf who accompanied
Celeborn into exile [from Aman!]. And in yet another late text, JRRT made Celebrimbor into "a Sinda who claimed descent from Daeron" [
Of Dwarves and Men].
Cough. What was the question? Oh yes.
Anyway, as I say, I hold JRRT to his published idea, and according to his own commentary,
even Christopher Tolkien thinks that his father would have felt bound by this as well (that is, had his father remembered).
So for me, Feanorean it is!
The note: in this note JRRT explained that
1) though a son of Curufin and inheriting his skills, Celebrimbor was an Elf of wholly different temper
2) and during his dwelling in Nargothrond Celebrimbor grew to love
Finrod (of course!)
3) Celebrimbor was aghast at the behaviour of his father Curufin, and so, he would not go with him, and
4) that later he became a friend of Celeborn and
Galadriel.
The note also relates that Celebrimbor's mother had refused to take part in the Rebellion of Feanor, and had remained in Aman with
Finarfin's folk, so it appears at least, that Celebrimbor was born in Aman.
So what was he doing in the period of time under consideration. I'm guessing he had a good long nap.
The text from
Unfinished Tales called
Concerning Galadriel and Celeborn states that Galadriel and Celeborn had with them a Jewel-smith of Gondolin (repeated in the
Elessar Tale), but Christopher Tolkien briefly mentions that the text was later emended to make Celebrimbor a Feanorean (again, as Tolkien would revise for the Second Edition of Appendix B). . .
. . . anyway, for myself at least, so far, I see these at two distinct ideas; in other words, making Celebrimbor a descendant of Feanor doesn't necessarily mean he had ever been to Gondolin --
and if the Elessar Tale were to still be in play, all we would need is
Enerdhil back in Gondolin.
Some speculation there, yes, but I do find it interesting that the note mentions that Celebrimbor later became a friend of Celeborn and Galadriel.
And at some point here, maybe Celebrimbor
had the aid of a handsome hero passing by!