Review of publicly available academic, industry, and NGO research as well as first-hand personal accounts of the impacts of magnesium mining and metal processing.

Summary

• Magnesium (Mg) is produced in the form of magnesium compounds as well as by itself as magnesium metal. The metal has multiple useful qualities including being lightweight

• Magnesium resources are virtually limitless given its presence in seawater, although currently the metal is usually produced from ore

• Despite its abundance, Mg is a critical mineral for multiple countries due to China producing around 87% of the world's magnesium

• This supply risk became clear in 2021 when China shut down many processing plants to hit annual carbon emission targets

• All Mg production processes create magnesium slag, a dust which is hard to control and lands on the ground, forming a crust which is detrimental to plant life

• In addition, China’s use of coal creates various emissions problems; and some scientists estimated the global warming impact of magnesium metal in China to be ∼60% higher than aluminum

• Recycling could provide benefits (e.g. only 5% of energy), but good systems for post-consumer magnesium recycling don’t exist. Most Mg is recycled when aluminum beverage cans are recycled, as it is included there as an alloy, or from pre-consumer industrial scrap