The antiques included a jar and human bones in Sikhoraphum district.
Muay Maichai, 60, the first person who stumbled upon the items, said she always visited the area. On Saturday, she saw a part of the jar sticking out from under the soil, so she decided to dig it up. Later, she discovered human bones nearby.
Yesterday, department officials visited the area after they were contacted. They excavated the items and took them to Phimai National Museum in Nakhon Ratchasima province.
The officials informed locals that the rare find dates back 1,500 years to a prehistorical period, seeing that the jar and bones were graved together in a funeral.