Thanks, Himring!  It's clear in TTT and ROTK that the phial is far more than an ordinary lantern.  I guess I see the phial as a collaborative effort between Celebrimbor and Galadriel, presumably aided by Nenya.  The particular craft of capturing light within gems, lamps, etc. does seem to belong only to the Feanorians, and the source of the light (E's star) is unambigous.  And we know that C was (at the very least) close in friendship with G, and probably gave her all number of things over the years (not just Nenya)!   I probably bent the canon a bit -- G does tell Frodo "For you I have prepared this." -- but hopefully only a bit :).