Can you imagine losing a diamond ring, a surfboard, a floor rug or your parent's ashes at the airport?

What if you never got the item back?

If you have lost something valuable at Brisbane Airport, chances are it will be up for public auction this week among hundreds of lost property items.

Surfboards, handbags, laptops, rings, suitcases full of clothes and designer sunglasses are just some of the items to be sold in the airport's first public online auction, with proceeds going to Australia Zoo's Wildlife Warriors.

Brisbane Airport says it makes every effort to return each item before auctioning it off. ( ABC News: Claire Boughey )

Even quirkier wares will go under the virtual hammer from Wednesday evening: a karaoke stand from Samoa, a rice cooker and an array of baby car seats, crutches and walking sticks.

Brisbane Airport spokeswoman Leonie Vandeven said items that had not been returned to their owners within 60 days would go under the hammer.

"We get many weird and wonderful items that are unfortunately lost at Brisbane Airport — false teeth … we've had prosthetic limbs," she said.

"A lot of the weirder things don't end up at auction — they're donated to charity."

Pickles operations manager Rhys Jones tests out a karaoke machine. ( ABC News: Claire Boughey )

Ms Vandeven said visitors to Brisbane had lost human ashes at least twice, but those were returned.

"On the odd occasion we've actually had the cremated remains of people handed in to lost property," she said.

"Airports are very busy places, they're environments of high emotion — good and bad — and people sometimes get quite stressed.

"They rush to get a flight and leave things on a chair."

Ms Vandeven said the airport made every effort to return each item before auctioning it off.

She said about a third of all lost items were ultimately returned to their owners.

Ms Vandeven said if anyone saw their lost personal treasures now listed for auction, and they could "prove beyond doubt it's theirs, they would be happy to reunite them.

"Unfortunately if it's gone to auction, by the time they want it back we hope they will be happy in the fact that their item has gone to good use," she said.

The bidding, to be conducted by auction house Pickles, began at 5:00pm on Wednesday and will run for a week.