Ed Hartz joined other members of the Marble Institute of America (MIA) on a tour of several marble quarries in New England. Geologic forces push calcium carbonate deposits such as limestone deep below the surface of the Earth, where heat and pressure form Marble crystals. A similar geological process forms granite from silica deposits. Later geologic forces lifted the marble and granite to the surface where it is economical to quarry the stone for architectural and artistic uses. The conditions that form each marble deposit are slightly different: the ratio of calcium carbonate to magnesium carbonate varies, the presence and amounts of other minerals varies, the pressure and temperature to form marble crystals varies, and the sequence of events that cause inclusions and veining varies. The conditions that form each granite deposit also vary; the duration of temperature and pressure as the silica deposits rise and cool determine how large the quartz crystals will become. The percentage of other minerals such as feldspar and aluminum and the fractures that allow inclusions create the patterns that make granite such an interesting material. The MIA members visited the quarries to see first hand the subtle differences throughout each quarry and the differences between the quarries.
The tour set out in a gray rain in Barre, VT, for the Rock of Ages Visitors Center in Graniteville, where company Vice President Bob Campo showed Ed the monument and mausoleum manufacturing process up close. Rough granite slabs of the desired color and pattern are cut to the required shape, polished, engraved and sand blasted to produce the individual monuments. Following the tour of the manufacturing facility, Ed visited the E. L. Smith Quarry, also owned by Rock of Ages. Granite has been quarried here since 1880. One familiar monument constructed with this granite is the World War II Memorial that opened in 2003. Ed saw diverse granite monuments at the Hope Cemetery in Barre.
A visit to the Vermont Granite Museum of Barre supplied more history and details about the quarrying and manufacturing of architectural granite. At the next stop, Granite Importers owner, Jake Colgan, accompanied Ed an the rest of the MIA group as they walked through the fabrication facility, which was in the process of working on giving a polished finish to curved pieces of Cambrian Black granite for the Mandarin hotel in Boston. Black shows every flaw and curved surfaces are difficult to polish so Ed was very interested to see the techniques that produce the highest quality finish.
The marble part of the tour included the Danby marble quarry, operated by Vermont Quarries Corp. of Rutland, VT. Luca Mannolini, General Manager, led a tour of their facility and the Imperial quarry, in Dorset Mountain, which is the largest underground marble quarry in the U.S. Danby marble was used to construct the U. S. Supreme Court Building, Jefferson Monument and several other prominent buildings, but 90% of the marble has been used for kitchen countertops. Ed examined the facility that produces 30,000 square feet of marble per month, and took photographs of the giant blocks before they are cut into slabs.
Ed and the MIA tour visited the Marble Museum in Proctor, VT, a unique resource of the extent and variety of marble from throughout the world. Philip Gawet of Gawet Marble and Granite recounted the history of the marble industry in Vermont, which is illustrated in the photographs in the museum. The museum is housed in a former factory and warehouse and includes the adjacent abandoned quarry. The worked face of the upper portion of the quarry is dramatically reflected in the rainwater that has collected in the pit. Another highlight of Proctor is a recently restored marble bridge that you will cross on the way to the museum.
The final stop on the tour was the Bethel White quarry, owned by Rock of Ages. Bob Campo explained that the stone quarried there is some of the whitest granite in the world, and a premium quality material. One characteristic of this stone is that it can be cut in either direction and still look the same.
The tour provided the depth and detail of information about New England marble and granite that is only possible with direct face-to-face discussions. Ed and the rest of the MIA group are extremely grateful to their hosts for sharing their knowledge and expertise.
The entrance to the marble mine
At the top of an open pit marble quarry
Descending the marble quarryŚnotice the tiny people
The working level of the marble quarry
Ed Hartz at the working level of the marble quarry
Approaching the Marble Museum
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