Mohawkite, a rare compound of silver, copper, arsenic, cobalt, nickel and iron, is found only one place in the world - in the Mohawk-Ahmeek area of Keweenaw County in Michigan. This 2.1-ounce nugget has been polished to show its pretty silvery tone with a hint of gold. This is from a stash, which was mined in the 1950s. It had been sitting in a garage for a long, long time.