The tradition of leaving coins on the headstones of military personnel can be traced as far back as the Roman empire.
A coin left on a headstone or at the grave site is meant as a message to the deceased soldier’s family that someone else has visited the grave to pay respect.
Leaving a penny at the grave means simply that you visited. A nickel indicates that you and the deceased trained at boot camp together, while a dime means you served with him in some capacity. By leaving a quarter at the grave, you are telling the family that you were with the soldier when he was killed.
According to tradition, the money left at graves in national and state veterans' cemeteries is eventually collected, and the funds are put toward maintaining the cemetery or paying burial costs for indigent veterans.
In the United States, this practice became common during the Vietnam War, due to the political divide in the country over the war. Leaving a coin was a practical way to communicate that you had visited the grave than contacting the soldier’s family, which could evolve into an uncomfortable argument over politics relating to the war. Some Vietnam veterans would leave coins as a “down payment” to buy their fallen comrades a beer or play a hand of cards when they would finally be reunited.
In these more current times, coins still show up on military markers and nonmilitary markers along with other small items, be they plaques resting atop the sod or tombstones erected at the head of the burial plot. These small tokens are left by visitors for no greater purpose than to indicate to the family that someone has visited that family member.
On nonmilitary headstones coins, especially pennies, are favored by those who wish to demonstrate that the deceased has not been forgotten. A nickel means you went to school together, a dime that you worked together, and a quarter that you were there when they died.
In most cases, coins are collected in late fall and used for cemetery improvements.