Shard trading?

Well my friend is still new to the hextech crafting process(he didn't even know how to re-roll champs) and He has an elderwood hecarim skin shard, what i was wondering, is if it would be possible to trade skin shards? now, to ensure you guys don't lose money from ppl buying hextech chests, you could only trade, say, once per month, and since people still need to get essence, or they just can't wait that long, they'll still buy stuff with rp. i know there are going to be flaws with this plan, but who knows? riot could find a way to make money off of this. but you'd only be able to trade skin shards for skin shards, and same goes for champ shards. oor, what if it costed essence to trade shards(depending on what type it is) any ideas? (also i'm not sure where this post would go, but i assume this is the best place)