Yes you can, I'm not 100% sure, but I believe that all the magic items at least will stay on the ground forever (the same with quest or usable items and notes + books)
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Bordin Steelaxe
The greatest Dwarf in history!... with an axe of steel
Greetings from the humble adventurer Bordin Steelaxe
The greatest Dwarf in history!... with an axe of steel
D@mn UBB codes!
Putting it on the ground is not very safe. Putting it in _something_ usually will keep it indefinitely. There are various nooks around the promenade that you can use or you can use your stronghold once you get it.