Dimension stone (Mt. Airy)
Mining (quarrying) - water jet / wire sawing

A high pressure water jet in operation. This jet cuts 3-inch wide vertical cuts. The water is directed on the rock at 40,000 pounds per inch through jet openings. The jet arm moves up and down and can cut to a depth of 21 feet. The vertical cut is made by moving the jet horizontally along the yellow horizontal boom. The vertical lines are closely spaced drill holes from the previous quarrying method.  The image to the right shows the smoother cut surface from the water jet cutting. 

Beginning in late 2000, the North Carolina Granite Company began a new quarrying process. The process involves water jet drilling in combination with horizontal wire sawing.

The new process allows quarrying faces to be developed throughout the property, extends reserves, and provides a more efficient quarrying process.

The image below shows the smooth vertical face resulting from jet drilling. The dark vertical slot in the left background of this image is another vertical jet drilled cut.  The wire saw loop is placed in these slots and the floor of sections up to 40 feet by 40 feet are cut by horizontal wire saws.

The vertical faces were cut by a jet drill. The horizontal floor was cut by a wire saw.