well, I have to say the rarest thing I own is...ummm...hmm...Oh! My rare stone collection! I used to collect rocks back when I was little, and now I have all of them turned into animals of different types.
Also, I have an antique handmade whale carving from the early 1900's. And a hand-knitted one-of-a-kind rug from early in the 1800's. It was used for traveling by my grandmother's great-grandmother (I don't know how many great- s that would be. lol)
hmmm...what else.....oh, a copy of the Brothers Grimm from the 1800's as well! It's a childrens version of it, which means it has all the blood and gore, but there's pictures. lol.
...I think that's it! But I'll write back if there's anything else.
Take care of that Colt Erasmus. Rare items, I've got a few old English coins from the turn of the century. I've got a Soviet Mosin Nagant from 1945, but that's not rare. I think I've got some other things but I can't quite recall them just now.