Salvation Army Capt. Linda Payton told Miami's WTVJ-TV her office got a call from the anonymous woman about 1 p.m. Friday.
"She said that she had just left something in the kettle in front of Kmart and that it was something special," Payton said.
So off to Kmart, Payton went, and she brought the kettle back to the office.
"Inside the kettle was, wrapped in a rubber band, a $50 bill and inside the $50 bill was a note, and inside the note was a ring," Payton said.
The note said: "They need more than I. Do good! A Friend."
The ring, which features two diamonds ad a sapphire, was immediately appraised at $2,000, Payton said.
Last Christmas holiday season, someone deposited a gold nugget in a Miami kettle with a note expressing a similar sentiment. The nugget sold for $4,000 at auction.
"It's just wonderful for the community, we're just the conduit, they're the ones who will receive it," Payton said.