Just as the title says, I've had quite a few miscellaneous quests disappear from my quest log, and it's starting to bother me now as I fear they'll never come back. I can't say for sure how many (or which) have disappeared, but I know for sure that the quest where I have to take the unusual gem to an appraiser was one of the ones that seems to have disappeared very recently. There may be more, but this one stands out in particular.
Is there any reason why this has happened? Clashing quests perhaps or have I lost it/them forever? :(.