The first time this happened I though I had just made a mistake, but it just happened again.  I tried to create an item exchange with some of my spare crystalline ice.  The ice is gone from inventory (correctly), but the exchange doesn't show up in my active auctions/exchanges page, I don't have a log report for the exchange, and the item I was asking for (spirit in a jar) hasn't been added to my inventory.  As far as I can tell, my crystalline ice has just vanished.

I just tried testing with your user data and I see two active exchanges "Crystalline Ice - Spirit in a Jar" in your exchanges. They are also publicly visible for everyone. Did you create more than two of them, or are these two the trades in question?

These are the two in question, I just can't see them from my end.

Well, that's weird.  I just tried relaunching my browser, and now I can see them, so I can only assume the problem was on my end.  Thanks Angel!

Glad that the problem resolved itself!