A New York City woman has been reunited with her diamond engagement ring thanks to the efforts of an altruistic stranger, NBC News reports.

Mother-of-two Jill Fink was certain she'd lost her ring forever after she left it in an Upper West Side park in Manhattan. Fink had taken off the ring to apply sunscreen on her 2-year-old daughter and had forgotten to put it back on.

On her way to work a couple of days later, she discovered that the ring was missing.

“I looked at my hand…and realized I wasn’t wearing it,” Fink told ABC News. “So I ran back upstairs but it wasn’t in my room. Then, I had a flash of putting sunscreen on my daughter and realized it was [lost] two days ago.”

Assuming her ring was lost for good, she called her husband in tears.

But luckily for Fink, the ring was in the safe hands of another Upper West Side mom named Michelle La Plante.

La Plante told NBC News that she found the diamond ring in the park near the swings where her daughter was playing. She picked it up, thinking that the owner would soon return.

But when no one did, La Plante took the ring home and began a search for the owner -- putting up fliers in the neighborhood and posting lost and found ads online, including one on Craigslist.

"If that had been my ring, I would have gone out of my head," La Plante said.

According to NBC News, a colleague of Fink's found La Plante's Craigslist post online after hearing about the lost ring. Fink immediately sent out an email with the ring's description to her Good Samaritan.

La Plante knew right away that she had a match and called Fink back with the good news.

“She picked up [the phone] and started sobbing and so did I. It was this amazing, happy ending,” La Plante told ABC News.

The two women have since met and Fink's ring is back on her finger.

Fink, who gave La Plante a gift card as a token of her gratitude, told ABC News that she still “cannot believe that such a good person found [the ring].”

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