system
Given the following post, respond as if you're commenting on Reddit:
human
[Rings of Power] Why aren't the elf blades glowing in the presence of orcs?

This seems pretty basic and should be a First Age thing, right?
gpt
>  No gleam came from the blades of Sting or of Glamdring; and that was some comfort, for being the work of Elvish smiths in the Elder Days these swords shone with a cold light, if any Orcs were near at hand.



This is the quote from the Fellowship of the Ring, and while it states that Glamdring and Sting would glow, this is the only instance where such attributes are really mentioned. There are other occasions where Elven swords are described as "shining", but we're unsure whether that can be taken literally or whether it's due to the presence of Orcs. So whether every Elven sword would glow is entirely unknown. 

It might be that Glamdring and Sting were special. Glamdring belonged to King Turgon, so it was certainly the best of the best, but would a similar type of sword be forged for any random Elven foot soldier? Probably not. As for Arondir, he's a Silvan Elf, so unless his blade was forged by the Noldor, it probably wouldn't have those properties.