Jewellery with a value of $16,000 has been dropped off at the City Mission charity shop in Victoria Avenue, Whanganui.
Shop manager Michelle Wilson said a woman had dropped in a parcel of stuff and told staff it was "a donation for the mission". But she is certain the jewellery was included in error.
"When we opened it one of the staff immediately knew it was valuable" said Mrs Wilson.
She doesn't think the donation was deliberate, given the way the jewellery was packaged.
Three experts have examined the jewellery and agreed on an estimated value of $16,000.