57 stories below the surface...wow!Grand Saline sits at the top of the largest and purest salt dome in the United States, which Morton Salt has been mining since 1931. Seismic tests have shown the dome descends to a depth of 20,000 feet.
The Morton Salt Mine in Grand Saline is the town’s largest employer and one of three rock-salt mines Morton operates in the U.S. The salt deposit is 250 million years old. Mining is currently being done 57 stories below the surface.
https://www.east-texas.com/grand-saline-texas.htm
One big piece of rock salt! You could make a lot of homemade ice cream with that much salt.
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