This is that rarest of copper habits, a so called wire copper from Upper Michigan's historic copper district. The specimen features a slender, elongated Copper crystal 3.3 cm in length and another small cluster of Copper crystals right near the top of the piece, on calcite matrix that both protects and displays the wire. So called wire or rope copper actually is a strange, elongated, spinel twin form of the native metal. This habit is particularly rare from Michigan, and then to get one on matrix...very hard, indeed. This is from the Midwest and Copper suite of the Keith Williams collection, a friend of ours who recently retired (side fact - Keith did my first five figure deal with me on a group minerals, back in 1993. Strangely, as a result of buying a good rock that another major collector had dithered on and came back for later, I met the legendary collector Dr. Ed David when he tracked me down and angrily demanded the right to buy back the rock he had missed at a fair profit. He later became a great friend and teacher to me - Ed was truly amazing! Part of his collection is now in the Houston Museum).