Calcium is the fifth most abundant element by mass in the Earth’s crust and the third most abundant metal after iron and aluminium.

As a highly reactive metal and reducing agent, calcium is rarely found in its pure metallic form. Demand for calcium metal is dominated by the steelmaking, alloying and refining industries.

The main feedstock for calcium production – limestone – is widespread in nature, yet only three countries in the world produce calcium metal. China is by far the largest producer, followed by Russia and the United States.

Limestone mining in China and Russia is reportedly associated with significant environmental degradation, impacts on local communities and social discord. However, calcium production is only a tiny fraction of the overall use of limestone, which is also a key feedstock for the cement and concrete industries, among others. Calcium purchasers may benefit from forming partnerships with other industries in order to increase leverage on their supply chains, to support positive environmental and social change in limestone production.