LUNAR CRITICAL MINERALS

Critical minerals are non-fuel resources that are essential for the United States economy or national security and have vulnerable supply chains. There are many lists of critical minerals with minor differences, but the most pressing minerals are generally agreed upon. Demand for critical minerals is expected to double or even triple by 2040, driven mostly by spikes in the energy and transportation sectors linked to the energy transition. China has developed a near -monopoly on mining and particularly refining many critical minerals, especially rare earth elements and semiconductor metals. Recently, they have begun to put export controls on some of these critical minerals, increasing the importance of finding alternative supplies.

This has led to suggestions that critical minerals could be sourced from the Moon. Concentrations of critical minerals in lunar materials have been measured in meteorites and returned samples, and are almost universally lower than ore grades in terrestrial deposits, sometimes by many orders of magnitude. Even for the minerals that approach terrestrial values, the cost to establish a lunar mining operation would be monumental and is unlikely to trade favorably against alternatives like sea-floor mining. However, there is a shortlist of minerals that have a combination of high supply chain risk, relatively high lunar concentrations, and low amounts mined each year such that a significant fraction of the supply could be transported in a low number of trips. There is a case to carry out further exploration for these minerals on the Moon, particularly for rare earths in so-called KREEP rocks, and for platinum group elements in layered igneous intrusions. Understanding and controlling access to these lunar resources could become more important on longer timescales whether they are used within an in-space economy or possibly returned to Earth.