Stone is one of the earliest materials used by man. Natural deposits of granite, marble, slate and other stones have served a wide range of applications, from practical to artistic.
The stone cutting process consists of two broad steps: extracting stone from the earth and then treating and shaping it for its desired purpose. Over time, a number of different tools and methods have been used cut stone.
Early Stone Age
The most primitive method of stone cutting involved simply hitting a soft stone with a harder one. This process dates back to, appropriately enough, the Early Stone Age.
At the time, stone was used primarily as a weapon. Early “tool kits” included hammerstones, which were used to do the work, and core stones, from which smaller flakes were struck to provide cutting edges.
Ancient Egyptian civilizations constructed pyramids, obelisks and some of the more stunning examples of stonework found in history. The Egyptians’ quarrying technique consisted of digging a trench around a block of stone, then cutting beneath the stone and pushing it out.
Once the stone was extracted, workers cut a series of holes with a hammer and chisel. Water-soaked wooden wedges were inserted into the holes, where they expanded and split the rock. Bronze tools were used with limestone and other softer rocks.
Saws have long been a traditional tool for woodcutting, so it was inevitable that man tried to use them on stone as well. Unsurprisingly, saws made from the hardest materials available were still of little use on anything but the softest types of stone.
Marble Cutting and the Helical Wire
Marble cutting techniques took a huge step forward in the 19th century with the development of the helical wire. A continuous loop of steel wire was attached to a pulley moving five to six meters per second.
The abrasiveness of the wire cut through marble, allowing a greater degree of precision than had previously been possible. Helical wire cutting was refined in the mid-20th century, when diamond dust was embedded into the wire.
The quarrying process today begins with surface stripping, in which crawler tractors remove material covering the stone to be extracted. Sometimes blasting is done by drilling holes into the earth and packing them with explosives.
With CNC stone cutting machines, there are almost no limits to the objects that can be produced, from flat countertops to intricately-cut architectural pieces.