Dating back to 1885, Rock of Ages Corp. of Barre, VT, has grown into a stone-production powerhouse - with ownership of 10 active quarries and five manufacturing and sawing facilities in North America. The publicly owned company is a leading quarrier of granite in the U.S. and Canada, and it is among the world's largest manufacturers and retailers of granite memorials. While the majority of Rock of Ages' quarrying sites and fabricating plants are located in Vermont and the Province of Quebec, the company also owns a successful quarrying operation in Salisbury, NC.

Salisbury Pink granite - consisting of unique pink shading and fine grain texture - is primarily utilized for building work such as exterior cladding as well as interior applications, according to Robert Campo, Vice President of Sales and Marketing at Rock of Ages. Additionally, it is used for memorials and mausoleums in the U.S.

Rock of Ages acquired ownership of the Salisbury Pink quarry in 1997. With 50 workers and several supervisors, the quarry produces an average of 8,000 cubic meters on an annual basis. Equipment at the site includes Caterpillar 992 loaders, Tamrock drills from Finland - including 600 Slotliners and Commandos - Ned-Jet waterjets and Pellegrini diesel diamond wire saws.

Updating extraction methods

The quarry has recently been going through a transition to phase out the torches that have been used previously for channeling, according to Campo. “These have been gradually replaced with the diamond wire saws, slot drills and waterjets to produce more economically as well as being more environmental friendly,” he said.

Each of the methods Campo mentioned has specific advantages and disadvantages that determine under what conditions it is best utilized. Water is used in conjunction with each cutting method to suppress dust, control heat and wash detritus from the cut.

When slot drilling, a series of vertical holes 2 ½ inches in diameter are drilled approximately 4 ½ inches apart. After these holes are drilled, a 3-inch-diameter bit is then used to core the “web” - the small amount of granite that remains between the drilled holes. This “coring” process removes all of the granite between the holes, creating a channel between the mass being quarried and the quarry walls. As a result of this method, the channel has a corrugated appearance.

When using a diamond wire saw for channeling, a vertical and a horizontal hole are drilled with a conventional pneumatic drill so that they meet at a right angle. A strand of diamond wire is then fed through the holes, and the saw maintains the proper tension as the stone is cut by the moving of the entire saw unit away from the quarry face along the set of rails.

The third method of channeling used by Rock of Ages is the waterjet, which is powered by a portable diesel engine that is housed in a unit separate from the cutting unit containing the nozzles and tracking system. To begin, a pilot hole is drilled with a pneumatic drill - serving as the starting point for the waterjet wand. Oscillating nozzles shoot water at a pressure of 40,000 pounds per square inch. Unlike waterjets used in many other industries, this cutting method does not mix water with abrasive, such as garnet. The pressure of the water is the sole cutting agent. The automated wand containing the nozzles moves vertically, cutting at speeds of up to 40 square feet per hour.

According to Rock of Ages, benches at the quarry are typically about 40 feet long, 30 feet wide and 15 to 17 feet in height. The average size of a block measures about 10 x 5 x 5 feet and weighs over 20 tons.

Market / projects

The primary export market for Salisbury Pink granite is Asia, but Europe and the Middle East have now become interested in the product as well, said Campo. In Asia, the granite is favored for its light color and consistent texture.

Among the most recent uses of Salisbury Pink granite was the “Phase Two” project at the Hamburg Airport in Germany, where it was employed as flooring in a new terminal. Moreover, the material has been employed for many other high-profile projects worldwide.

“The signature project for this stone was completed in Abu Dhabi in 2004 and early 2005,” said Campo. “This is the Emirates Palace Hotel project, which required over 3,000 cubic meters of Salisbury Pink blocks for the exterior of the building, which is actually about a mile long.”

Supplying Salisbury Pink granite to high-quality jobs such as the Emirates Palace Hotel confirms to Rock of Ages the reasons for making a commitment to this quarry. “We made a major financial investment in equipment and manpower in order to meet the anticipated demand for this premium granite,” said a statement made by the company. “As predicted, Salisbury Pink has grown to be the stone of choice for many projects throughout the world. Its unique pink shading and fine grain have placed it in the top of its class.”