I'd be very hesitant about having something created by a 'normal' wizard as an Item of Power. The description in text is:
"an artifact that goes beyond the ephemeral items created by spellcasters and alchemists. This is an artifact with an ancient story, often drawing its power from some vast supernatural entity of old"
Personally it's my thought that an IoP would require some 'epic' story as to it's creation/origin. A holy reliquary, a Sword of the Cross, a Faerie Blade, a relic of a dead god, or weapon of a long dead hero, would be by my book a option for a IoP, even a family blade, passed down the centuries, and imbued with a fragment of the life-force of those who had borne it, but I wouldn't allow an average PC to just make a IoP, at least not without jumping through a heck of a lot of hoops.