SF Holding Co., China’s biggest express-delivery firm, is set to open a gold vault in Hong Kong to tap demand for storage as the city pushes forward with plans to become a precious-metals hub.

The courier is planning to open the custodian vault within its complex near the airport in October, said people familiar with the matter. One section will comprise safe-deposit boxes for high-value assets, while the other will mainly be for precious metals, with a capacity of 50 to 100 tons, they said, asking not to be named as they’re not authorized to speak to the media.