In the Upper Peninsula rock exposures may be found in every county - sandstones in northern Chippewa and limestones in the southern part of the county; limestones, some gypsum, and shale in Mackinac; sandstones in Luce, Alger, Marquette, Baraga, Keweenaw, Ontonagon, Gogebic, Dickinson and Iron; limestones in Menominee, Dickinson, Delta and Schoolcraft counties. The igneous and metamorphic rocks, with their wealth of copper, silver, and iron ore, crop out to make the wild and picturesque scenery and the gorges of Keweenaw, Houghton, Marquette, Dickinson, Baraga, Iron, Ontonagon and Gogebic counties as well as the highest peaks in the State-the Huron and Porcupine mountains. In the dumps and rock piles of the mines, minerals and rocks from far underground may be found.
Throughout your tour of the Upper Peninsula you will want to look for Lake Superior agates, found on the shore of Lake Superior, especially after storms. Besides their inherent hardness and fine luster, concentric banding (eastern Upper Peninsula and the Keweenaw) is a definite clue to the identity of specimens. Agates feel waxy to the touch.
If you walk on private property along the Lake Superior beach, you should obtain permission of the property owner. His rights extend to the water's edge, regardless of water level fluctuations. Permission is not required, however, if you wade in the water, just off the beach. Submerged bottomlands of the Great Lakes are open to the public.
Starting at the Straits of Mackinac your route turns westward. Stop at Pointe Aux Chenes about ten miles west of St. Ignace. Look in piles of stone along the highway. You may find some mottled brown and white gypsum or some beautiful specimens of very fine needle-like crystals with a satiny luster. This variety of gypsum is called satin spar.
If you have time it would be worth while to make a side trip to a quarry about nine miles east of Trout Lake where excellent and abundant samples of chert and flint can be obtained. Chert and flint can also be obtained in the old quarries at Manistique if your route is along the northern shore of Lake Michigan.
Tours of the Upper Peninsula often take the vacationer by one route and return him by another. If you go first by the route along Lake Superior, stop in the Whitefish Point area and check the beaches for agates. Banded agates can be found in the Eastern U.P., especially in places such as the beaches of Paradise and Whitefish Point and the beaches north of Newberry (food and lodging).
Excellent specimens of "bog iron" ore, limonite, can be found about three-quarters of a mile south of Seney and also along the highway west of Seney, (Food and Lodging) near the Seney National Wildlife Refuge.
At Marquette you enter the iron-mining district and the region of igneous and metamorphic, or the crystalline rocks which make up the western half of the Upper Peninsula. Veins of green epidote, an inch or more in width, show in the granite cuts of Sugar Loaf Mountain a few miles northwest of Marquette and in the granite outcrop near the Dead River Bridge not far from the ore docks in Marquette.
Nearly two billion years ago, the area west of Marquette was very likely as high as the Alps. The rocks you see along the lakeshore are part of the eroded roots of a mountain system similar to alpine-type mountains. Geologists speculate that this region may even have been as high as the present-day Himalaya Mountains, the tallest peaks in the world.
In the Marquette area, at the Superior Mine and the Jackson Mine Locations, you should fine druses of Goethite.
When you're in Marquette, go northwest on Presque Isle Avenue to the end. At the point you will find agate, fortification (Lake Superior); Calcite; Chalcedony geodes to 5" in diameter and Jasper.
At Ishpeming (Food and Lodging) you really get into the "mineral country." Beautiful light green talc, a very soft greasy-feeling mineral, can be obtained near the Ropes Gold Mine, a few miles north of Ishpeming. At the same locality, serpentine, a much harder dark green mineral, that may be streaked with white dolomite, can be found. Mixtures of serpentine and dolomite, calcite or talc are known as "verde antique marble". Vein quartz is abundant at the Michigan Gold Mine a few miles west and north of Ishpeming.
Some fragments of quartz contain tourmaline, a black shiny mineral in long needle-like crystals. Other minerals such as barite, a white platy heavy mineral, and manganese-bearing minerals such as pyrolusite, manganite, and psilomelane, can be collected near Ishpeming. Specimens of iron ore, hematite, can be obtained at any mine.
"Jasper Hill," in Ishpeming, is a convenient place from which to obtain specimens of beautifully banded jasper and specular hematite, known as jaspilite. Be sure to see Jasper Knob, the worlds largest gemstone which is composed completely of jaspilite. Jaspilite probably creates the most beautiful and interesting rock formations in the entire state of Michigan.
In the Ishpeming area, there are several old mine sites that will attract your attention.
While still in Ishpeming, take SR-28 and Division Street through the city then turn right at the foot of Jasper Hill. You will see Hematite; Red Jasper, and Jaspilite.
For the Ropes Gold Mine, go west from Ishpeming on US-41 to Cooper Lake Road, turn right and go 2.5 miles, left on CR-572 for less than 1 mile, walk 0.3 mile to Ropes Gold Mine. You will also see Serpentine here.
In Negaunee a monument has been erected marking the place where the Jackson Mining Company discovered iron ore in 1845, the year following the first discovery of iron ore in the Upper Peninsula (September 19, 1844). The monument is made of every kind of rock, ore, and mineral found in the Iron Country.
In the Negaunee area, stop at the Baltic Mine dump for massive Rhodochrosite, check at the Cambria Mine for Hematite, kidney, massive, specular and Steatite (Soap stone).
Also in the Negaunee area at the Lucy Mine, search for Barite, nice crystals; Manganite, metallic gray-black in blocky crystal clusters.
After leaving the Ishpeming-Negaunee area, take highway M-95 to Republic, eight miles south of Champion. (Lodging) This trip may add several minerals to the collection. Specular hematite and magnetite are abundant on the old mine dumps. You may find crystallized quartz in openings in the specularite, and occasional crystals of staurolite in a light-colored mica schist. Good specimens of feldspar can be found at several places. A lead-colored, soft, foliated (in scales or leaves) mineral, molybdenite, has been found in quartz veins near Republic, but it is in too small amounts to make a search for it really worth while.
In the Republic area you should also find Beryl, Red Jasper, Jaspilite and Tourmaline.
Your next stop should be at Champion. (Lodging for the Champion and Republic mine sites) On the old rock piles on Beacon Hill a number of minerals can be obtained. Specular hematite, a variety composed of thin, very lustrous, scales of hematite closely pressed together, is the type of iron ore found at this locality. Magnetite is abundant and dark red garnet crystals are partially embedded in lumps of magnetite. Long, slender interlaced prisms of black tourmaline have also formed on the magnetite. Tourmaline crystals, when broken, show a spherical triangular cross section, that is, the prisms have three sides but the sides are curved. Fine parallel lines are on the long prism faces. Be sure to pick up fragments of quartz from the Champion rock piles. In many of these quartz crystals you will see slender prisms of tourmaline. A brown mineral with cleavage like that of calcite is occasionally found at Champion. This is siderite, a carbonate of iron. At the Champion Mine, it is possible to find sapphire and sericite.
Head for the Athens mine near Champion. There the red and dark brown of the heaps of iron ore minerals are in striking contrast to the yellow and buff surface clays, once the deposits on the bed of an old glacial lake. The red mineral is hematite. Some hematite is dense, hard, and crystallized in long fibers. Masses of large fibers are known as "pencil ore." Some crystals arrange themselves in oddly shaped masses of concretions know as kidney ore. Some hematite is soft, as you will find when your clothing is soiled if you are not careful how you handle the powdery, non-lustrous ore. Goethite, a brown iron mineral that is really hematite plus water, may be found in beautiful orthorhombic crystals in cavities. Nearby is another dark brown mineral, never found in crystals. It is known as limonite. It may not be a separate distinct mineral but a fine-grained goethite.
Now take a short side trip through the village of Michigamme, cross the bridge at Michigamme Beach and follow the road on the south side of Lake Michigamme for about one and one-half miles. You will see a rock-cut on the north side of the road in which the dark-colored schist rock has a pimply appearance due to small crystals of staurolite which are harder than the body of the rock and stand out in relief as the rock is worn by wind and weather. The staurolite can he easily recognized because so many specimens have two crystals crossed (twinned) to form an X.
Garnet may be found in the Michigamme area at the Mount Shasta mine.
Should you return from the Upper Peninsula by way of the Southern Route (U.S. 2) attractive mineral specimens can be obtained in the marble quarries at Randville and Felch in Dickinson County (Lodging). Slender white satiny-looking prisms of tremolite and grass-green blades of actinolite are found in the white crystalline dolomitic marble. At Felch a pink feldspar can be obtained from a dike rock which cuts across the marble. Where the dike is in contact with the marble, brown and blackish serpentine is found.
The Iron County mine rock piles have Hematite and Specularite. The mines are near Amasa, Crystal Falls, Iron River, Mineral Hills and Stambaugh.
Much of this information is from Rocks and Minerals of Michigan
By O. F. Poindexter, H. M. Martin and S. G. Bergquist, Michigan
Department of Natural Resources, 1971 and