One Tough Crush

Pit & Quarry

John Powell knew a challenge loomed when he first encountered the material Sergeant Stone planned to crush at a startup site in Corning, Ohio.

The material, which Powell perceived to be limestone, was as hard as any he had seen within Ohio during his 19 years with Eagle Crusher Co. In fact, after Powell sent initial samples to Bowser-Morner, a testing firm within the state, one came back with a compressive strength of 49,360 psi.

That's abnormally high for limestone. A second Bowser-Morner test was later conducted, revealing a Mohs hardness of 5. More limestone has a hardness of about 3, so Sergeant Stone's material technically has more characteristics of siltstone than it does limestone.