I've got a really nice shield that I'd like to make nicer by making it Fine. But I'm worried that it's other properties are unique, and thus, I might never find another by the time I have access to the Superb or Exceptional enchantments. Can I replace/upgrade from Fine to Exceptional or Superb at a later time?
Yes, you can.
Rules regarding enchanting, from what I've gathered are as follows:
- you can have only one enchantment per category
- enchantments are restricted by the anvil symbols - each piece of equipment can hold a maximum of 12 anvils.
- enchantment not available for custom enchanting (and therefore not listed as taking a slot under any category), unique ones that some weapons you can aquire already have, do not influence it (except for the rule above) - they will not be lost whatever you do.
- enchantments are not exchangable - once you get one that's it, slot of that category forever stuck in the choice you made. Quality category however is an exception to that rule:
- You can freely exchange enchantments in Quality category provided you change it to an enchantment that is equally powerfull or more so (the new one has to have greater or equal amount of anvils than the one already there). For example Fine can be exchanged into Accuracy 2 (and the other way around ad infinium), but Exceptional can only be changed to Superb
Well, I agree with bharal, there are details about the cost which are not clearly and explicitly stated, which a person would want to include in the answer to leave out any uncertainty. I can see how you would think of "exchange freely within quality" as good enough, but it does not clear up the uncertainty 100% for a reader. When I was reading this I really wanted to see the words written down that stated that the old before upgrade enchantments do not still contribute towards the overall enchantment cap, something like this.
If you have a basic unmodified item like a full plate mail, then you add a fine enchantment the total enchantment listed will be (2). You can upgrade the fine to something of equal enchantment cost or higher within the same category. When you exchange an enchantment like this, the old cost is no longer factored into the overall enchantment cap listed on the item. This means that if you take that fine plate mail and add the enchantment (exceptional - 4) the overall amount of enchantment anvils on that item will be (4) only and the fine benefits and contribution to the enchantment anvils cap will disappear entirely.