I think when you open the chest, it would show a button you to sell the rune or to keep it in your inventory.
Maybe you chose to keep it in inv. (maybe that makes that unsellable)
I've sold mine when that appeared.
Thanks for the replies! 
I see the emoji icon now when I'm replying 
But when you make a new forum thread, the box in which you type the message has no emoji option 
well rip for the thread create part
Nop, there’s no way to sell runes anymore. Sometimes the website glitches and you can sell them after opening a chest, but otherwise you cant sell them.
Im keeping them all so i can sell them when this bullsh** is over :)
in 3 steps
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I've not been actively using this site for a while and when I tried to sell a rune I obtained from a chest, I realised that there was no button/option to sell it anymore, unlike before. Has Gamehag stopped this practice of selling runes for gems? Some runes are completely useless and I would never consume them ever, so being unable to trade them in for gems is a right bummer. P.S. I notice the forum format has also changed. How does one use emoji now?