According to The Official Gazette of Turkey, who has attained the age of 18 passengers and non-citizens of the Republic of Turkey can bring up to 5 kilograms of raw gold standard in weight within a year together.
According to the regulation made, it was decided that the import of precious metals can only be made by the Central Bank and the companies that are members of the Precious Metal Exchange.
https://www.resmigazete.gov.tr/eskiler/2020/03/20200303-10.htm