Banks have started trial gold imports directly into the Shanghai free trade zone ahead of the launch of a gold exchange there, threatening to further obscure the level of buying by the world's top consumer.
The bulk of gold bought by China used to flow through Hong Kong, making its export data a useful proxy for Chinese demand as Beijing treats data about imports of the precious metal as a state secret.
But Reuters calculations using export numbers from data provider Global Trade Information Services show that China's direct gold imports jumped to nearly 150 tonne in the first quarter.
Excluding Switzerland, which did not disclose country specific data in 2013, direct imports nearly doubled in the period from a year ago.
The number does not provide a complete picture as some exporters do not provide gold trade data and others do not break down their exports by country.
"If gold enters China via Shanghai then it is not going to be easy anymore to draw conclusions about Chinese demand by just looking at Hong Kong data," said Carsten Fritsch, an analyst with Commerzbank.
The Shanghai Gold Exchange the world's biggest platform for physical gold trade is in talks with foreign banks and producers on the new exchange in the city's pilot free trade zone.
The exchange is set to launch physically deliverable gold contracts, with the metal allowed to be stored in vaults in the free trade zone.
Banks had already started imports through the free trade zone, said a source at a gold-importing bank in China. "Shanghai should play a far bigger role once the international exchange is open," said the person.