BOSTON (AP) — What started with a widow quietly dropping her wedding rings into a Salvation Army donation kettle has spawned spontaneous acts of jewelry generosity this holiday season.

Boston's feel-good Christmas story took a new twist this week when an anonymous donor originally from Australia placed a diamond-encrusted cross pendant valued at $1,500 in one of the charity's trademark red kettles.

The donor said she was inspired by a widow who gave her wedding and diamond engagement rings earlier this month and asked that the proceeds be used to buy toys for poor children. That was followed by another widow who donated $21,000 — 10 times what the rings were worth — so she could return the donated jewelry to the original owner.

"There's something special happening here in Boston," said Salvation Army Capt. Myron Smith, who found the latest gift of expensive jewelry while emptying a kettle outside a supermarket in suburban Brookline.

"We're blessed and overwhelmed with this latest donation," he said. "It's great to see Bostonians inspired by acts of generosity during this holiday season."

The Salvation Army said Tuesday the Australian woman donated her pendant to thank Bostonians for their warm welcome when she and her son recently relocated to the city.

It was accompanied by a note that read: "I needed to find somewhere for us, particularly my son, to be happy again. We had visited Boston several times and always loved it here. Since relocating, people have been so warm, friendly, kind and accommodating to us, and I have been trying to think of a way to give back to the people of Boston."

The donor said she was trying to figure out how best to help the poor when she saw news accounts of the widow who gave her rings in memory of her late husband.

"This inspired me, and I have enclosed this diamond cross, which is symbolic of Christmas, and ask that you sell it and use the money to help those less fortunate this Christmas," the unidentified Australian wrote.

The Salvation Army said the two widows met Monday and the rings were returned. It said the woman who donated the $21,000 told the rings' owner: "See what you started?"

Salvation Army spokesman Drew Forster said the charity has found jewelry in its kettles in past years, "but it's usually been an accidental thing."

Something nobler is happening in 2014, Forster said.

"Caring is contagious, and that's what we're experiencing here," he said. "People are seeing these kind acts performed and they want to get involved. These are priceless gifts to them, and that makes it all the more special."