Lake Ellen Kimberlite Pipe Locality
An exposure of an 18-acre diatreme of tuffaceous kimberlite breccia, located along a logging road west of Lake Ellen. Discovered in 1971, this is the first- and best-known of more than 20 kimberlite bodies that have been discovered in northern Michigan. Most are concentrated in a belt extending from this locality to Hermansville to the southwest. None have proven to be economically viable sources of diamond, however, microscopic diamonds have been found.
The Lake Ellen kimberlite was intruded into the surrounding Proterozoic Hemlock Volcanics formation approximately 180 MYA. In addition to occasional eclogitic mantle xenoliths, Ordovician limestone xenoliths are common among the rubbly, greenish-gray kimberlite breccia. The nearest outcrops of this limestone are 40 miles east, indicating that the formations once extended west to Lake Ellen.
The most well known kimberlite location is the Lake Ellen diamond exploration location North East of Crystal Falls, Michigan
The majority of the possible Diamond bearing strata ocurr in a line from Crystal Falls East to Hermansville./Powers area. Shawn Carlson, a geologist involved in the Diamond Explorations of the U. P. in the recent past. Shawn has suggested that no significent commercial discoveries have been made to date. No diamonds have been found in quantity, or larger than 1mm in the explorations.
However, the Lake Ellen location does have Ruby-Red Pyrope Garnets, and Magnesium Ilmenite of gem quality. Garnets can be over one inch, and a one half inch Garnet as well as many smaller ones, with fantastic color. The Hermansville location yielded beautiful Peridot from the drill core. However, this location is under water and is not accessible.