A man has been reunited with a treasured collection of baseball cards and jewelry worth nearly $50,000 after spotting the stolen goods listed for sale online.

Steven Ortiz was riding a MAX train from Portland International Airport to visit family in Oregon on Sunday when he accidentally dropped his backpack while deboarding at the Beaverton Transit Center.

Surveillance footage showed another rider — later identified as 34-year-old Dawn M. Castro — quickly snatched up the bag, according to the Beaverton Police Department.

Inside the backpack was jewelry and 10 trading cards for famed athletes including Joe Montana, Michael Jordan, and Kobe Bryant, as well as a rare card of Yankees center fielder Mickey Mantle worth a reported $5,000, police said.

Ortiz, a 61-year-old card collector from Wisconsin, says he was planning to have the cards professionally evaluated ahead of a sale. But there was no price in the world for the three gold necklaces and two diamond rings, which had belonged to his wife, Kathy, before her death.

Ortiz was distraught — until his son searched social media and found the cards listed for sale. Oritz arraigned several meet-ups, but the purported seller backed out each time, he said. Detectives say they caught up with Castro anyway, back at the Beaverton Transit Center around noon Monday.

The cards and jewelry have now been returned to their rightful owner, according to police and Ortiz.

“I wanted all the stuff back, because it’s mine,” he said. “But I’m just glad I got the jewelry back, because that has significant sentimental value to me.”

Castro faces a first-degree aggravated theft charge.

She was previously convicted of first-degree criminal mistreatment and sentenced to 1½ years in prison in 2016. She has open cases for allegedly unlawfully possessing methamphetamine and shoplifting from a grocery store in Multnomah County.

—Zane Sparling covers breaking news and courts for The Oregonian/OregonLive. Reach him at 503-319-7083, zsparling@oregonian.com or @pdxzane.

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