Shanghai resident Du Chengyi and his family of three have had to spend six extra days in Antalya, Turkey, to appear in court on charges of smuggling cultural relics during their trip.

The 20 euro ($27) stone Du bought from a vendor at a scenic site was to blame.

"It (the stone) looks like any piece of normal marble, with both sides ground to rectangles," Du said about the brick-sized stone he brought as a souvenir during the vacation with his wife and mother-in-law.

"We never asked for a receipt during our nine-day stay in Turkey because of the difficulty with the language, and we were never told that tourists could not bring the stone out of the country," said Du, who arrived in Shanghai on Wednesday afternoon with his family.

Since March 22, Du and his family have spent a day in Antalya's police bureau and have been dealing with the court. They said they learned at Antalya International Airport last Thursday that the "souvenir" they bought was a piece from a cultural relic, and they were arrested on smuggling charges because they could not produce a receipt.

Du said he hired a local attorney to handle the case and that he was informed the next court date would be on April 10. "I'm not sure how much I could be fined, but a French woman was just deported and charged 15,000 euros for a piece of stone she picked up at the seaside a few days ago."

Du blamed Turkish authorities for his situation because they didn't take any initiative to inform foreign tourists of the law.

GoTurkey.com, however, Turkey's official tourism portal, warns that exporting antiquities or antiques from the country is a serious crime and there are severe penalties for those who attempt to do so.

In addition to the warning, the website also mentions that "for valuable gifts and souvenirs, proof of purchase is necessary, together with receipts showing that any currency used in the purchase has been legally exchanged".

According to Liu Yang, a Beijing lawyer who specializes in relics preservation, Turkey had more than 5,000 cases involving smuggling of cultural relics in 2010 alone. "The legal system related to smuggling of Turkey's cultural relics is very strict," Liu said.

As for Du's case, he said that if the matter could not be resolved through diplomatic channels, the only option is to prove that the family was unaware of the law. "A large amount of evidence and a witness, such as the vendor who sold the stone, must be tracked down in Turkey to prove Du didn't know," he said.

Shen Jie, of Shanghai's SAL travel agency, said most tour groups would be informed of the potential consequences of not asking for a receipt for purchases in countries such as Egypt and Turkey. "They'd be advised to shop at formal stores rather than street venders," said Shen, who's in charge of the agency's Turkey tourism. "Du headed to Turkey as an individual traveler rather than group traveler."

Zhou Yan, who works as a translator for a German court, said that although this was the first case in Turkey in which Chinese were involved, such cases are common among European tourists visiting Antalya.

"German travelers are the main source of Antalya's tourism revenue, so the German embassy is very familiar with the process of rescuing its nationals from the city, and German travel agencies always warn their tourists before their departure," said Zhou, who regularly vacations in Antalya. "The only reason it took so long for this to happen to a Chinese is that not many Chinese visit Antalya."

Zhou also said that from the experience of European countries' foreign ministries in dealing with this kind of case in Turkey, there is no way to prove whether a piece of stone is a cultural relic because "by law, the (Turkish) people determine whether an object is a relic or not".

In the meantime, the Shanghai Tourism Bureau reminded Chinese tourists on Tuesday to be aware of foreign laws and customs before heading overseas.