Le Dinh Yen, deputy director of the Phu Quy waste treatment factory in the central province, said on Tuesday rings and other jewelry that were retrieved have been returned to a woman living in Phu Quy Island.
He said the woman, who asked not to be identified, came to the plant on Monday and said her daughter mistakenly threw away a bag containing the jewelry and some documents the afternoon before.
She only discovered it after returning home in the evening, but the garbage had been taken away by then.
Yen put five workers on the job, but by then trash from all over the island had arrived at the site, and amounted to around 20 tons.
He called a halt to the waste processing and also had garbage trucks searched.
The bag was eventually found after a 10-hour search.