Why pick up a lonely pebble or flintstone and put that on the resting place of a loved one, when you can pay 25 bucks to have a personalized, clean, nicely-shaped stone instead?
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Why do we leave a Stone on the Monument ?
The practice of leaving small stones or pebbles on the monument of a loved one to commemorate a visit to the grave site is a tradition that developed hundreds of years ago and was passed down from one generation to the next.
Although most scholars can find no foundation in religion for the custom of leaving a stone by the grave site, the practice of doing so is presumed to signify the rebuilding of the monument. In early days, people did not have the ability to carve gravestones. Instead, they marked the grave site by placing many stones and rocks at the burial site. Over time, the rocks were disturbed by natural processes and the grave site required rebuilding to be identified. Thus, when technology permitted the creation of a gravestone, the practice of placing a stone at the monument became a tradition of love and respect for the departed. While widely practiced by those of the Jewish faith, many religions and cultures still practice this custom.