I was crafting a topaz gem from 3 flawed topaz gems, I was in a hurry so I tried to time walking away from the vendor exactly with the end of the gem creation, and when I looked in my inventory (10 seconds later as I went straight to my stash to store it) I did not have the three flawed nor single regular gem in my inventory. I don't have enough gems atm to recreate this. It was in single player normal, act 3. Thanks :)