elena_tiriel gave me the following quote
The figure by the door moved. In the dark without moon or stars a drawn blade gleamed, as if a chill light had been unsheathed. There was a blow, soft but heavy, and the door shuddered.
'Open, in the name of Mordor!' said a voice thin and menacing.
The Fellowship of the Ring, LoTR Book 1, Ch 11, A Knife in the Dark
and remarked "Did you catch that about the Nazgul's sword gleaming, like Sting does?"
So, just how did a Nazgul get a glowy blade? ;-)
Day 267
Taken InIn times past, his forefathers had been gifted with many treasures. From the Dwarves, mail that was light to wear yet could turn the heaviest blow. From the Elves, blades that did not blunt with years and use, and warned of approaching danger. From the lesser Men of these conquered shores, labour to raise strong walls and lofty towers.
It was only fitting this offering should come to him, who had studied long and garnered mastery and wisdom greater than any other of his race.
Inclining his head graciously, Abattârik reached out his hand to take the ring from Annatar.