History of 3M Wausau
The 3M Wausau Facility was purchased from Wausau Abrasives in 1929. It was the first 3M manufacturing facility purchased outside of Minnesota and is the oldest, currently operating, manufacturing facility for 3M in the world. The original manufacturing facility was located where the existing one still stands in downtown Wausau. The original quarry was located on the west end of Rib Mountain. Initially the facility manufactured grit for sandpaper.
In the 1930’s, 3M was approached by a shingle manufacturer to mine and color rock for the shingle industry which led to the production of roofing granules. It was determined after a few years that the rock used for roofing granules from the Rib Mountain Quarry was not suitable for asphalt shingles. 3M Geologists searched for a more suitable rock to be used for roofing granules and found the site known today as the Greystone Quarry, which has been operating since the 1930’s. Construction of the Greystone Crushing Facility began in 1952 and was finished in 1954.
Today rock continues to be mined from the Greystone Quarry which is sent through a series of crushers and screeners until each rock is the right particle size for roofing granules. It is then sent through a coloring process to add colored pigments to meet the customer’s needs. Granules are loaded in railroad cars or semi-trucks for delivery our customers.
Rib Mountain from downtown Wausau, Wis.