able to get duplicate artifacts if buying from a store first

[Shoob]

if you buy an artifact from a store it is not marked as found, meaning you can find it on the ground or in the store again later.

[Fela]

I just found 2 everfilling mana pots, so either those are not unique or if they are generated at the same generation run on a level, duplicates are also possible.

[Shoob]

yeah you can do it that way too, got 2 staffs of destruction that way.