Stunning Proterozoic Stromatolite with Rhodochrosite

This stromatolite is at once, ancient (Precambrian), beautiful, and unusually colored. The unsual, rare and asthetic characteristic is a significant content of Rhodochrosite. Rhodochrosite (MnCO3, Manganese Carbonate - whose name means rose-colored) is a very attractive mineral with an absolutely one-of-a-kind, beautiful color that is a gemstone in crystal form, and otherwise used in various jewelry applications. The Rhodochrosite here is the red blotches in the upper half. Although it can be an ore of manganese, it is its ornamental and display specimen qualities that make it a very popular mineral. The color of a single crystal can just astound the observer with its vivid pink-rose color that seems to be transmitted out of the crystal as if lit from within.

Coming from the Chocolay Group in an area known as the Chocolay Hills located southeast of Ishpeming, Michigan, this stromatolite dates to the Lower Proterozoic, some 2.2 to 2.4 Billion years old. The specimen that has been hand-polished to a mirror finish on one side exhibits intricate banding prototypical in stromatolites. The fossil is the evidence of the great oxigenation event that ranks among the most important phenomena that drove evolution of life on Earth.