April 24, 2010
The Alabastine Mine is a former gypsum mine in Wyoming, MI, a suburb of Grand Rapids. After mining stopped, part of the mine was paved and lighted, to be used as a storage warehouse. It is still operatedas a warehouse today, under the name Michigan Natural Storage. The rest of the mine is still in its original condition (dark, damp, and muddy).
Kreigh Tomaszewski, field trip chairman for the Indian Mounds club, has been able to arrange access to the mine through Dr. Kevin Cole of Grand View State College. He invited a number of clubs in the area to join them on a trip. There were only a few requirements, other than a restriction on the number of collectors: hard hats, a change of shoes (so as not to track mud through the clean paved portions of the mine), and at least 2 sources of light. Children 10 years of age and older were allowed.
WE started to assemble in the parking lot around 9:15 AM, where Kreigh checked our equipment and collected the $2 fee required by the mine owners (to defray the cost of keeping the lights on for us). It had rained quite hard on my way to the mine, but it wasn’t raining when we met. It was nice to go on a field trip on a rainy day and not have to worry about the weather!
At 10 AM we went into the building and got on the elevator. Kreigh explained that after exiting the elevator, the doors must be left closed so that it could be called from above, if needed.
Here’s the group on the elevator. Kreigh is on the right. There are two more not in the picture, myself and another who was also taking a picture.
When we got to the bottom (about 85 feet down), Kreigh led us through the lighted and paved portion of the mine to the beginning of the collecting area. There we changed into our work shoes, parked the carts some of us used to carry our equipment, turned on our lights, and got to work.
The tunnels exposed a series of layers:
Near the roof is a layer of shale, which contains gypsum crystals and fossils- shark teeth and coprolites, and some shark bone.
Next is a layer of crystalline gypsum, ranging in color from almost white to an attractive orange color.
Below the crystalline gypsum is a layer of cryptocrystalline gypsum- alabaster. This again varies in color from almost white to orange.
Finally, below the alabaster is clay. This is quite gummy, making walking on the tunnel floor difficult, and making climbing up to the upper layers even more difficult.
The photo below is of collectors working on the shale layer. They did find some shark coprolites.
I left the mine around 1 PM, although many stayed until they had to be out at 4 PM. I understand that even then, Kreigh had to walk back about a mile into the tunnel to tell a few die-hards that it was time to go!
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