Morwen, yes that's from the Silmarillion of course, and Tolkien was still musing on the matter. See
William Cloud Hickli's post above, which is based on text from the
Later Quenta Silmarillion II,
Morgoth's Ring.
'Now the Quendi had possessed weapons in Middle-earth, but not of their own devising. They had been made by Aule and sent as gifts by the hand of Orome, when it became known to the Valar that the Quendi were beset by prowling evils that had discovered the places of their dwelling beside Cuiviénen; and more were sent later for the defence of the Eldar upon the Great March to the shores of the Sea. ...' JRRT LQS (52a)
In 52b Feanor still makes a secret forge and etc in any case. See also Christopher Tolkien's commentary that follows these sections in the book.