I have obtained it in previous games but I can't sell it to Delvin in my current one for some reason...I've sold it before in my other games. I've obtained all of the Other Trinkets that you can sell to him(That I Know of) :

-Queen Bee Statue
-Honningbrew Decanter
-East Empire Trading Map
-Model Ship
-Dwemer Puzzle Cube
-Bust of the Gray Fox

In my other Games I never found The EETC Map, But I could Sell the Eye, But now I can't. Can you only Sell him six items?

Weird...I have the right eye of the falmer still (Feels too grand to sell to a vendor). The left one is sitting on the shelves in the guild. I think I gave it to Delvin for it to appear there? Didn't know there were so many unique things to collect to put on display via Delvin. Thank you! More things to collect and find.

Well that's just it Though, I can't sell it to him like the rest for some odd Reason...Not in my Current Character at least.

Edit: Not sure if it's worth Mentioning...But I also have a Bee in a Jar. Seems Like an odd enough item...Dunno what it's for though.

I had the same issue, and I'm guessing that you can indeed only sell him six pieces.

They should get some bigger shelves

It could be that you can only sell six pieces but I've also heard the eyes are somewhat buggy when selling to Delvin at any rate. (I can't sell them either.)

I use the two gems to help fill up the empty vault along with gobs of jewels, a full chest of ebony ingots, full chest of gold ore, full chest of gold ingots, and various other loot.

The place is looking much better now. Damn right, the Thieves guild is back! Your guildmaster appreciates you litttle thieves you.

Well when I initially obtained the Left Eye, all of the other Items you can Sell had turned in the quests on the spot...


Probably stupid of me I know.