According to the provisions of the Mainland Customs, diamonds are neither supplies nor necessities during the trip and thus belong to the scope of goods. So such diamond should be declared at entry and exit. Otherwise, it shall be classified as smuggling. People may be sentenced to jail.
据内地海关规定，钻石非旅客于行程中的用品或必需品，故属于货品范畴，出入境时需申报，否则或列作走私，情况严重可被判入狱。