Unable to Receive "A Complete Collection" Achievement SOLVED

So, according to the collection lists, I have found all of the items for the museum. Every one of them has their own unique description, not reading "Gunther can tell you more...", telling me that there is at least one of everything in the museum. I was able to place each item and find all of the Lost Books without any grief or bugs, and all seems well. Pictures are attached to show precisely what I see for my collection lists as well as placement in the museum proper.

... So why is Gunther still sending me out to go "treasure hunting" when I've found everything that is to be found? What is it that I'm missing, if at all?

 

I'm only counting 94 items there?
I don't see Elvish Jewelry on there in your museum, meaning you found it, but never donated it

 

O.O Yes! You're right! I remember getting it, but I must not have donated it...! Thank you, I'll keep an eye out! I'll go ahead and remove this thread too, since it's not a bug issue any more.

EDIT: Yup, that was the last piece I needed. I must have just glossed over it in the collection lists, thank you so much for pointing that out. I feel really silly now, too. ^.^"