She gave him just a 30-cent tip, but a New York cabbie didn't hesitate before tracking down a passenger to return 31 diamond rings she had left behind.

"I'm not going to take someone else's money or property to make me rich. I don't want it that way," said driver Osman Chowdhury, who is from Bangladesh.

He was even reluctant to accept the $100 check the passenger offered as a reward, eventually accepting it to cover the fares he lost while trying to locate her. But the 41-year-old cabbie did have a message: "I'm proud of what I did so that people know New York taxi drivers are honest."

What he did started on Monday evening, when he picked up the woman at a hotel in midtown Manhattan and drove her to an apartment building about 15 blocks away. She gave him $20 to pay the fare and asked for $9 back.

Hours later, at about 10 p.m., three other passengers with luggage discovered the woman's suitcase when Chowdhury popped the trunk open for them.

Chowdhury first drove to the building where he had dropped off the woman. But he had no idea in which of the many apartments she might be and didn't want to cause a disruption by knocking on doors.

He took the suitcase to the Manhattan headquarters of the New York Taxi Workers Alliance, a drivers' advocacy group to which he belongs. He and the alliance president looked inside and found two display cases with 31 diamond rings inside.

"I saw flashing, and I said, 'Oh, my God! Diamonds!"' Chowdhury recalled. "I was shocked. I was trembling."

They also found a small luggage tag with a Texas telephone number they called — the home of the woman's mother in Dallas.

The woman, who said she was a jeweler, got the gems back when she arrived at the alliance office around midnight Monday — incredulous at her luck. The woman, from Dallas, asked that her name not be made public.

Chowdhury was a contractor in Bangladesh until he came to the United States 15 years ago. He does not own a cab but rents one.

"I enjoy my life. I'm satisfied," said Chowdhury, who is single.

He said he didn't mind the meager tip, and it never occurred to him to keep the diamonds.

"All my life, I tried to be honest," the soft-spoken cabbie said. "Today is no different."