First, let me say that this credo is cursed. Study times on everything that it asks for are ridiculous. Best one so far are prisms, 10h or so, but i had it just once. Some quests ask for 100h+ of study time, cmon!
So to the point of subject: Hand impression. An item that in it's own very descriptions allows you to choose betwen fired and unfired version. Unfired = 2h+, fired = 32 ridiculous hours of study.
So, credo asks me to study it, fine. I did and IT DID NOT COUNT for unfired version.
Bug.