INDIANA LIMESTONE--WORLD CLASS STONE RESOURCE

Indiana, Oolitic, or Bedford Limestone are trade names for the preeminent U.S. dimension limestone. Salem Limestone has a long and excellent history. It is mined in a limited (35 x 5 mile) belt of south central Indiana from the Mississippian age Salem Limestone. Deposited in a shoals complex, it is characterized by well-washed sand-sized grains, mostly fossil debris, and occurs in deposits from 20 to 80 feet thick. It is a variably porous free stone with excellent physical and aesthetic properties that make it well suited for architectural use and carving. Stone is graded on particle size, color, uniformity, and strength.

Mining began in 1827 and annual production grew to several hundred thousand cubic feet by 1870. Architectural tastes, economic conditions, and technology control production. Since 1990 from 2.3 to 3.9 million cubic feet were mined annually with values from $22 to $47 million. Originally valued for its load bearing capacity, the stone now is mostly used for appearance, durability and ease of working for cladding, accents, prefabricated panels, or sculptures.

The stone has had large cultural effects. Indiana Limestone has been used in thousands of buildings including iconic structures such as the Empire State Building, Washington Cathedral, and Pentagon. It is chosen for institutional structures and prestigious buildings such as State houses, court houses, libraries, and churches. It has a pleasing color, buff is preferred, and texture and has an excellent record of durability, physical strength, and beauty.

Local limestone industries have generated innovations such as new belt saws that improve productivity and allow underground mining. Traditional methods of shaping stone have been augmented by computer-controlled tools. Computer controlled cutting is also common.

Appreciation of the Indiana Limestone industry has led to local efforts to honor and preserve stone heritage. Area museums offer displays and programs about Indiana Limestone. Parades, fieldtrips, and festivals honoring the stone trade are held annually, as is a Limestone Carving Symposium. Efforts are also underway for a Limestone Heritage Park. Other reuses of the mines and mills are being studied. We should recognize the stone internationally. The district is an excellent candidate for a Global Heritage Stone area.