Should this only get artifacts from your own graveyard? Most white "return from graveyard" cards limit what you can grab to your own graveyard, while black can grab things from wherever.

Damn iPhone double posted. :(

Is that strong enough to warrant the cost?

The point is that it's out of color, not whether it's strong or not.

I don't think that reanimating artifacts from your opponent's graveyard is so far out of white's color that I don't mind breaking it. It's just not a part of the color pie I think is all that important.

But taking things from other people's graveyard feels like stealing, which makes it feel black.

Generally speaking, white either returns all artifacts to the battlefield under their owner's control (Open the Vaults, Roar of Reclamation) or returns an artifact card from the graveyard to the hand (Razor Hippogriff, Treasure Hunter). Returning your artifacts from the graveyard to the battlefield is white and blue (each gets one card that does it (Bringer of the White Dawn and Argivian Restoration, respectively) and then there's Protomatter Powder, which needs both). Historically speaking, stealing artifacts from other people's graveyards is unquestionably black (Beacon of Unrest and Geth, Lord of the Vault).

I know these distinctions don't seem like much, but I really think this fine minutiae is part of what keeps the color pie working. The simplest change is to make this only target your graveyard. Otherwise, I'd prefer it in black. I suppose the case could be made for blue, since blue likes to steal things, too.

Finally (sorry for the long post), if you're going to target any graveyard, it needs to say "Put target artifact card..." instead of "Return target artifact card...". You only return things from your own graveyard (Zombify vs. Rise from the Grave).

This should just be your graveyard.

I agree that the fine points of color distinction are important, I just don't think this is one of them, but I seem to be the dissenting opinion on this matter.

Could this maybe be an instant then?

I'd be wary of this as an instant, but you'd really need to playtest to see if it was broken. If you're in heavy white, an instant would be very strong. If you're spending , then an instant is fine. Possibly a little weak for the cost, even.