When Salvation Army volunteers in Massachusetts emptied the charity's red donation kettles last week, they found two rings and a note explaining that the donor, a widow, wanted them sold to "buy toys for needy children".
The anonymous note said that the donation - a diamond engagement ring and a wedding band worth about $1,850 (£1,177) - was being made in memory of her late husband.
According to the Boston Globe, it also said she was donating her engagement ring in the hope that "there's someone out there who made lots of money this year and will buy the ring for 10 times its worth."
Now it seems, her wish has come true. A fellow widow has bought the rings from the charity for $21,000 - or about £13,000 - way above their market value.
What's more, the generous lady, a former bell-ringer with the Salvation Army, wants to return the rings to their original owner in recognition of her generosity.
"I want to be involved in this because it's about the spirit of Christmas, the spirit of giving," the buyer said.
"My wish is that the rings can be returned to this woman who gave them up in memory of her husband for the sake of children at Christmas."
However, her gift will certainly help the Salvation Army in Massachusetts towards its statewide Red Kettle campaign goal of $3.36 million to support individuals and families in need.
Major David B. Davis, head of the Massachusetts Salvation Army, told the Daily Mail: "We're so moved and incredibly grateful to the generous individual who made such a loving and kind donation.
"This heartwarming gift boosts all of our staff, bell-ringers, and volunteers who are working tirelessly during the Red Kettle Campaign to encourage donations that help those in need."
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