Dolomite

Rocks & Minerals  Rock Thumbs

I recently took a trip to Rio, Wisconsin to obtain a rock sample out of the old Rio quarry. Upon arriving I found the quarry to be gone along with the hill behind that held the water tower. What was there was basically a blasting site and a huge pile of gravel along with some giant dolomite blocks and small piles of a mix of rock. I was lucky in some ways because I had access to rock that would normally be under the surface. The only problem is that I am not sure what layers the rock came from so it will take a bit of research to nail down the strata. Most of what was there was a mixture of dolomite and various stages of sandstone with some conglomerate mixed in. Some of the dolomite had small calcite crystals along with various types of iron crystals. I also came across a green coating on some that is in all probability glauconite mica. 

Rio Dolomite with what I believe are chalk layers

Glauconite Mica & calcite crystals on some of the dolomite

Copyright 2008 Kurt Larson--Last updated April 10, 2008