Armor question, those salvage items

when you kill a charr it might dropp its armor, i normaly just salvage it cause i have no idea what its used for. But sometimes its unidentifyed. So i unlocked a rune a while ago, a fire magic rune, and its quite usefull since i'm an elementalist. So i'v been holding on to it. Its called:

mind spark garb of minor fire magic. (Purple)

It has 30 armor. So i thought it might be worth something or maybe usefull.
Can someone please tell me what to do with this? What its used for, how much its worth etc. Thank you soo much!

You salvage it with an expert salvage kit to get the rune

Ohhh, nothing else? cant do anything but that with it?
Whats it worth?

Its worth as much as the rune trader is giving for the minor fire rune.
Runes for the core classes arent worth much except for a few exceptions. The vigor runes for example are usually worth more then the rest.

Once you get the rune if you want to use it to give yourself +1 in fire magic attribute you equip the rune to one of your pieces of armor.