I suspect there are two fairly simple options - I could make it so none can touch it except yourself and perhaps a few others of your choosing... or simply make it so that the item is essentially invisible to anyone who is not aware of it's presence in the first place.
Or if you would like, I can also hide it somewhere no one will be able to gain access in the first place.
May I ask, what is the nature of this artifact? What is the potential danger involved? It may be best to design a specific spell around it, if it is terribly volatile.