Sagot :
There are three types of weathering processes (erosion) that affects each gravestones appearance the three is; Chemical, Physical, and Biological. Weathering processes depend upon the presence of water, the temperature; the mineral composition of the rock and its chemical composition. Headstones are subjected to weathering by simply standing in a graveyard or cemetery. It is just also a matter of time in which the Headstones looks barely legible and others look sharp and clear.