Creepy grey UFO seen over Tombstone, Arizona

On March 17, 2017, a creepy UFO is appeared several minutes in blue sky over Tombstone, in Arizona.

Witness report:

Looking out towards open valley from silver mine in Tombstone Az and spotted object an focused in using zoom of camera. Object odd shaped and pure white. Hovered for at least 5 minutes. No detectable movement. Thought maybe was weird balloon but couldn't see any teather and if it was free it would have drifted. Husband seen it too but not with zoom. Someone stopped to talk and when we looked back it was no where in sight.