Limestone, specifically Salem Limestone, was officially designated as the "state stone" of Indiana by the Indiana General Assembly in 1971. Indiana Limestone or Bedford Limestone is a common term for Salem Limestone, a geological formation primarily quarried in south central Indiana between Bloomington and Bedford. Bloomington, Indiana has been noted to have the highest quality quarried Limestone in the United States. Salem Limestone, like all Limestone, is a rock primarily formed of calcium carbonate. The Limestone was deposited over millions of years as marine fossils decomposed at the bottom of a shallow inland sea which covered most of the present-day Midwestern United States during the Mississippian Period.
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The Native American Indians were some of the first people to discover Limestone in Indiana. It was not long before settlers used this rock around their windows and doors and for memorials around town. The first quarry was started in 1827, and by 1929 Indiana quarries yielded 340,000 cubic meters of usable stone. The expansion of the railroads brought great need for limestone to build bridges and tunnels and Indiana was the place to get it. American architecture of the late 19th and early 20th century included a lot of limestone detail work on buildings, but as architectural styles changed so did the demand of limestone. With the Arab oil embargo of 1973, the price of alternative building materials skyrocketed so Indiana Limestone reemerged as an energy efficient building material.
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Although rarely worn in jewelry, Limestone is a basic material for statues, ornaments and building exteriors and more recently as counter tops in businesses as well as homes. Today most Limestone is found in either block or slab form.
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