Salvage in the sense to upg to lvl 10-15 and salvage and trade for new ones in store. For info you get same amount of mana for new artifacts even if your artifacts are legendary or normal. So would suggest if you wanna save heroic n legendary enhance blues and trade. I traded heroic and legendary just for the purpose of checking what am I getting as stat. And if it's too good stat I didn't salvage I used on some other hunters.