Stefan Gottker, aged 34, says he was not even aware that his nine-year-old son had picked up the stone on a beach in the Mediterranean city of Antalya.
He was stopped by police at a security check at the local airport on 14 September, his lawyer Bilal Kalayci told AFP.
“We do not believe that the stone has any value as an antiquity,” Kalayci said, but added that an expert report by the local museum stated the opposite.
A picture of the stone, published in the local press, showed it could have been part of an ancient cornice.
Gottker will appear in court on 14 October, when he is expected to be bailed and go home, the lawyer said.
Trafficking in antiquities is frequent in Turkey, which was home to an array of ancient civilisations.
"We do not believe that the stone has any value as an antiquity"
Lawyer Bilal Kalayci
Turkey’s heritage is under threat, just as it is in Greece, Iraq, Syria, Iran, India, Cambodia and China.
There are more ancient Greek cities in Turkey than in Greece, and more Roman ones than in Rome.
The country has 50,000 villages, but 70,000 pre-Islamic sites.
A major cultural foundation in New York calculated that in 1989, Americans spent approximately $5 billion on works of art. Two billion dollars of this was spent on smuggled, stolen or fake works of art.
The total value of artefacts smuggled from Turkey was estimated to be between $300 million and $400 million. Only $2 million to $3 million, not even 1%, went to the Turkish looters.