Paramount Marble
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How Stone is Processed....

Stone has been the medium of choose for the edification of man from time immemorial; indeed, it has been the most used medium for the glorification of man's gods throughout the ages.  The Egyptians, Greeks, Romans, Byzantines, and other ancient cultures immortalized their gods with stone temples and tombs.  The ruins of their urbanization give testament today to the structural durability and beauty of stone.  Marbles used by the Emperor Hadrian to construct his enormous villa near Rome, and those used in the Parthenon in Athens are, among others, still quarried to this day.  Yet in those bygone days stone masons did not have the advantage of the specialized quarrying and cutting machinery we have today: diamond wire saws, diamond and silicon carbine cutting discs, gang saws, explosives, drilling equipment, polishing equipment and so forth.  The removal of blocks from quarries was an arduous and labor-intensive process, and the task of cutting stone into usable dimensions and installing it was no less daunting.  But ample evidence exists of how these ancient craftsmen were able to erect megalithic edifices carved from stone - many still considered to be the great wonders of the world.

The demand for natural architectural stone has increased so radically within the last twenty years that soon quarrying, hereto dominated by the Italians, Greeks and Spaniards, has become a major industry for many countries around the world: Brazil, Mexico, Canada, the United States, Guatemala, South Africa, Zimbabwe, China, India, Sri Lanka, Indonesia, and Australia to name just a few.  And whereas previously some of these countries sent raw blocks to Italy for fabrication into marketable precut units, most now have installed machinery to handle their own lines of production.  Brazil, for example, is now one of the world;s largest suppliers of granite, exporting both slab and precut tile material prepared in local manufacturing plants.  Despite this, however, Italy still presides as the largest exporter of stone, and is arguably the most prodigious supplier of stone fabrication technology and equipment.

Most architectural stone today is quarried from mountainsides or hillsides, open pit mines, or from "galleries" - great caverns within the heart of mountains.  The methods used are typically  the same for each quarrying condition in that the object is to ascertain the best material in terms of purity and fracture, to remove it in blocks large enough to yield slabs of a functional size for commercial use, or for cut-to-size tile lines.

The demand for these latter differs from market to market but the North American consumer requires predominantly square units in 12-inch, 16-inch, 18-inch or 24-inch, material but in North America are typically 20mm (3/4 inch) in thickness, and 4 to 7 feet tall by 8 to 11 in length.  Raw blacks are cut from the mountainside in a variety of ways, the most common being:

a) with diamond-impregnated steel wires

          b) with multi-hole drilling and small-charge

explosives.

         c) with large "chain-saw" or disc type machinery

Steel cables, impregnated with industrial diamonds, are probably the most used method for the extraction of blocks. Drilling equipment is used to bore into the stone face from two separate angles so that the two bore-holes meet.  As one can imagine, getting these two holes to meet depends largely on the expertise of the quarryman and their knowledge of the stone face and qualified predictions of the nature of the material within the mountain.  Once the two bore-holes meet, compressed air is used to blow through a cord to which is attached the diamond-impregnated cable. The cable is then pulled through, attached to a pulley on a "donkey" jig and joined into a continuous loop.  The jig, which sits on rails, is then backed up to cause tension in the cable, and motor which drives the pulley is then started.  Water is fed into the bore-hole with the moving cable to assist with cooling and the cable gradually starts to slice the rock

Another method of cutting blocks from the quarry face uses pneumatic drills to bore multiple holes close together in a straight line into which small charges of explosives are inserted, the detonation of which causes the material between the drilled holes to fracture, separating the large block from the hillside.  In days gone by, wooden wedges were inserted into these holes and then soaked with water.  The swelling wood caused the stone to split between the drilled holes.

Large chain saws with diamond impregnated segments are also used to cut into the quarry face to remove blocks.  Once the first slice or fracture is made, subsequent slices will be made at different angles to the original to separate a substantial portion of the quarry face.  Often these portions are tall and narrow and are toppled onto a bed of loose earth and small boulders to soften their fall.  Many methods are used to topple these gigantic monoliths of stone, one of which is to insert large pneumatic or hydraulic bags into the slot caused by the wire saw and inflating them with high pressure.  This causes the block to tilt past its center of gravity and topple.  Mechanical jacks are also used for the same purpose.  From these great blocks, smaller blocks are cut and dressed into roughly rectangular shapes, and are then transported by truck to the fabrication works for processing into slabs or tiles.

Once the raw blocks have reached the processing plant, they are loaded into "gang saws" - large machines with multiple blades spaced apart in accordance with slab gauge requirements.  Once again, these blades (similar to large hack-saw blades) are impregnated with industrial diamonds.  With water fed into them for cooling, the gang saws move backwards and forwards across the block descending slowly until the entire mass is cut into slabs.  The slabs are kept exactly in the sequence and are moved onto a polishing machine which lays each slab down in order for one face to be polished.  The polishing process, like all stone polishing of whatever magnitude, involves grinding the surface material away with successively finer and finer grit abrasive wheels or discs until the surface is mirror-smooth and can be buffed to a shine.  The polished slabs are stacked in their original order and set apart in bundles for quality control and packing.  The issue of sequence is important: when selecting slabs (or even tile material) for your project, you will find that each of the slabs in a bundle (or tiles in a box) are from the same block, bear the same coloration and hue, and have the same veins and surface features.  It is therefore extremely important that sufficient material from the same bundle or batch be available for your entire project PLUS AN ADEQUATE AMOUNT OF EXTRA MATERIAL since blocks of the same type of stone will vary considerably from location to location within the same quarry.