Decomposed granite of silica sand, silt particles, and clay. Different specific granite types have differing propensities to weather, and so differing likelihoods of producing decomposed granite. The parent granite material is a common type of igneous rock that is granular, with its grains large enough to be distinguished with the unaided eye (i.e., it is phaneritic in texture); it is composed of plagioclase feldspar, orthoclase feldspar, quartz, mica, and possibly other minerals. The chemical transformation of feldspar, one of the primary constituents of granite, into the clay mineral kaolin is one of the important weathering processes. The presence of clay allows water
Granite Railway past, many persons were injured — and some killed — while diving into the flooded abandoned quarries from great heights. The Department of Conservation and Recreation maintains the Quincy Quarries Reservation, which has facilities for rock climbing, and trails connecting the remains of the Granite Railway. Granite Railway The Granite Railway was one of the first railroads in the United States, built to carry granite from Quincy, Massachusetts to a dock on the Neponset River in Milton. From there boats carried the heavy stone to Charlestown for construction of the Bunker Hill Monument. The Granite Railway is popularly termed the