The weathering rates of gravestones are an indication of changes in the acidity of rainfall between locations and over time. The acidity is affected by air pollution and other factors, and could be used as a measure of changes in climate and pollution levels.

The Gravestone Project has two levels of data collection. The first is the location of graveyards, which requires the use of a GPS. The second is the measurement of the weathering of marble and other gravestones, which requires a micrometer. Citizen scientists can participate in either or both tasks.