I recently attended a webinar hosted by the Natural Stone Institute. The hosts took us through a virtual quarry visit to an Indiana Limestone quarry owned by Polycor in Bloomington, Indiana. Limestone by definition is a sedimentary rock composed of calcite plus calcium and/or magnesium. Ralph Morgan, the “Green Guy” at Polycor said that there may be 1,000 years’ worth of limestone in the Bloomington quarry alone! Indiana limestone is typically used for a variety of projects, including commercial properties, such as cathedrals, government offices, all the way to residential properties, such as garden features, fireplaces, step trails. The possibilities of using this stone are virtually endless due to its durability and sustainability.
Quarry operations are just as fascinating, with the geology of the limestone affecting its usage, varying from road rock all the way to rock used in the construction of buildings. Colors and grades can vary from site to site depending on the climate. In terms of methodology, Polycor uses both surface and underground mining to retrieve limestone slabs. Quarries usually use jet stream wet saws to extract the material out of the sites, which are then organized by color for current or pending projects.
The quarry tour was well worth the “trip”, and I highly recommend that anyone interested in the field of stone get a chance to see one in person or otherwise.
Polycor even created a walking tour guide about Chicago’s historical limestone buildings. Find it here!