Sharon Osbourne‘s very grateful a fan returned her massive diamond ring … and it clearly pays to be honest — ’cause she’s offering that fan a once-in-a-lifetime experience.

Here’s the deal … Osbourne revealed to her Instagram followers she lost her wedding at a retail store — but luckily, a Good Samaritan found it and chased her down in the parking lot to return it.

Now, Sharon’s repaying Bardsley’s random act of kindness by offering Bardsley and her family a VIP experience at a show her husband Ozzy Osbourne‘s participating in next year.

Moral of the story … keep an eye on the ground — ya never know which celeb’s jewelry might be lying there!