The Duobaoshan Copper-Molybdenum Mine and the Tongshan Copper Mine host ultra-large, low-grade porphyry copper deposits, with associated metals such as gold, silver, molybdenum and rhenium.

In 2020, a deep exploration program of the Tongshan deposit yielded a major breakthrough. According to the Exploration Report for Orebodies III and V of the Tongshan Copper Mine, which was reviewed and validated by the government in October 2025, the two orebodies added 3.65 Mt of copper resources, along with associated minerals—130,000 tonnes of molybdenum, 55 tonnes of gold, and 1,104 tonnes of silver. Orebody V alone contains 2.81 Mt of copper resources, making it the only ultra-large copper deposit discovered in Northeast China in the past four decades.

Both Duobaoshan and Tongshan are currently in production, with a combined daily processing capacity of 80,000 tonnes. At Tongshan, the underground mining project commenced production in April 2025. The deep development project at Tongshan is now being actively advanced. Once completed, it is expected to extend the mine life by more than 50 years, providing new momentum for sustained economic development in its host region.

Heilongjiang Duobaoshan Copper Co., Ltd. was established in 2006, with Zijin Mining owning a 31% interest. Through subsequent acquisitions in 2007 and 2016, Zijin Mining now holds 100% ownership of both the Duobaoshan and Tongshan copper mines.