The Criminal Court has ordered two pairs of elephant tusks owned by construction tycoon Premchai Karnasuta, his wife and an associate to be examined by Mahidol University to shed on the origin of the items.
The tusks are reported to be from African elephants which cannot be registered under Thai law.
Mr Premchai, 64, his wife Ms Khanitta, 64, and Wandee Somphum, 71, earlier pleaded not guilty to possession of two pairs of African elephant tusks at the Criminal Court. The tusks -- about a metre long and worth millions of baht -- were seized from Mr Premchai's residence in Bangkok in February.
Public prosecutors indicted the trio on April 11. They were charged by police with the unauthorised possession of carcasses of protected wildlife, smuggling and concealment of the smuggled objects.