Decomposed granite Decomposed granite Decomposed granite is classification of rock that is derived from granite via its weathering to the point that the parent material readily fractures into smaller pieces of weaker rock. Further weathering yields material that easily crumbles into a mixtures of gravel-sized particles known as grus, that in turn may break down to produce a mixture of clay and silica sand or silt particles. Different specific granite types have differing propensities to weather, and so differing likelihoods of producing decomposed granite. It has practical uses that include its incorporation into paving and driveway materials, residential gardening materials in arid
Godalming of the town centre steep hills reach 95 m (311.67 ft) AOD from 40-45m (131.23-147.63 ft) AOD in the town centre itself. In terms of rock and mineral structure, the soil is Gault Clay superimposed by Upper Greensand, Claygate Beds and Bagshot Sands; throughout the narrow east-west middle valley of Godalming and its wide northeast suburbs (Farncombe and Catteshall) the rocky head geological deposit is also found; angular pieces of rock and soil derived locally from the extensive frost-shattering of rocks and the subsequent movement of this material down valley slopes. Soil is mostly, i.e. on the upper slopes of