Dimension Stone - Sustainability of Dimension Stone

Sustainability of Dimension Stone

Dimension stone is one of the most sustainable of the industrial minerals since it is created by separating it from the natural bedrock underlying all land on every continent. Dimension stone rates very well in terms of the criteria on the ASTM checklist for sustainability of building products: there are no toxic materials used in its processing, there are no direct greenhouse gas emissions during processing, the dust created is controlled, the water used is almost completely recycled (per OSHA/MSHA regulation), and it is a perpetual resource (virtually inexhaustible in a human time scale). Dimension stone in use can last many generations, even centuries, so the dimension stone manufacturers have not needed a product recycling program. However, there are practical qualifications to and constraints on that sustainability. The dimension stone color and pattern can be changed by weathering when it is very near the surface. The color and pattern can also be changed by proximity to an igneous rock body or by the presence of circulating groundwater charged with carbon dioxide (i.e., limestone, travertine, marble). On the other hand, changes in color and/or pattern can be positive. For example, there are at least 14 separately trade-named varieties of Carrara Marble with many patterns (or no patterns) ranging in shade from white to gray. The presence of faults or closely spaced joints can render the stone unusable. These faults and joints do not have to be at odd angles in the stone mass. Closely spaced, wrongly spaced, or nonparallel bedding planes can make the stone unusable, particularly if the bedding planes are planes of weakness. If part of the stone in one area is unusable, there will be another usable part of the stone elsewhere in the formation. A quarry is not a short-term project unless it encounters one of these constraints. Examples of big, old quarries operating for more than a century include the Barre (VT) granite quarry, the Georgia Marble quarry at Tate, several of the Carrara (Italy) marble quarries, and the Penrhyn (Wales) slate quarry. A quarry will produce dust, noise, and some water pollution, but these can be remedied without too much trouble. The landscape may also have to be restored if quarry waste is temporarily or permanently placed on adjacent land.