The Keweenaw Peninsula is known as a source of native copper. A question I sometimes get is “What do you mean when you say NATIVE copper?”
Simply stated, the copper (mineral) is in its natural state and is not combined with any other minerals. A few elements can be found in their native state, but the only ones that are commonly encountered are Gold, Silver, Copper, Graphite, Diamond, and Sulfur.
Most of the native copper in the Keweenaw Peninsula does have a dash of silver in it, which made it more conductive, and therefore coveted by the burgeoning electrical companies back at the turn of the century. Native copper also requires very little refining. The copper mined in northern Michigan was just run through a stamp mill where the copper ore was smashed and the rock surrounding it was pulverized off. The copper then went directly to the smelters without any further processing.
The metals listed above are true metals, but I also see semi-metals in the U.P., such as Arsenic that combines with silver and copper to form Mohawkite. Mohawkite is an attractive find on some of the mine dumps, but care must be taken in handling and working with it due to the arsenic content. Mohawkite does make beautiful cabs that look like gold. The cabs will tarnish with time but can be re-polished with care and they make really distinctive jewelry. Lately I have been coating the Mohawkite cabochons with industrial epoxy. This prevents air from reaching the metals and thereby inhibits oxidation. (See also my post on Mohawkite of 9-14-09) Sometimes a treatment enhances a certain stone, making it a much better jewelry stone. This is what happens when Mohawkite is coated with epoxy. Some of my customers like the natural oxidation that is common with Mohawkite. I like the golden, shiny look of the coated stones. You can make your own selection.
We generally have many similar gemstones, other than those posted on this website. I am always willing to take a few photos of alternative pendants and send them to you. By the way, I love a challenge. What non-traditional gemstone pendant are you looking for?