Why are rare earth minerals important? They play an important role in the increasing demand for clean and efficient energy. Hybrid vehicles, permanent magnets, rechargeable batteries, wind turbines, compact fluorescent light bulbs, and catalytic converters — as well as cell phones, flat screen display panels, laptop computers, disk drives and more depend upon the unique properties of rare earth elements.
The U.S. Geological Survey, Mineral Commodity Summaries, January 2016 report was released and ironically there is currently an excess supply of rare earth elements. The report reads in part:
“In 2015, excess supply caused prices for rare-earth compounds and metals to decline significantly, and China continued to dominate the global supply of rare earths. According to China’s Rare Earth Industry Association, consumption of rare-earth oxides in China was forecast to increase from 98,000 tons in 2015 to 149,000 tons in 2020. In 2015, China’s consumption was led by magnets (35%), abrasives (18%), and catalysts (15%). Illegal production was cited as a major factor in declining prices. According to sources in China, despite Government efforts, illegal production of rare-earth materials was ongoing. China’s rare-earths industry was in the process of being consolidated into six major industrial entities. The rare-earth mining production quota for 2015 was set at 105,000 tons, unchanged from 2014. China ended its rare-earth export quotas, removed export tariffs, and began to impose resource taxes on rare earths based on sales value instead of production quantity. Through October 2015, China had exported 26,800 tons of rare-earth materials, a 20% increase compared with exports for the same period in 2014. Production of rare-earth oxide equivalent in Malaysia, derived from Australian mine production, was 7,750 tons through September 2015, a 55% increase compared with the same period in 2014. U.S. domestic consumption of rare-earth compounds and metals was estimated to be nearly unchanged compared with that of 2014. In October, the Mountain Pass mining and separation operations were idled indefinitely. Price declines were cited as a key factor in the suspension of operations. The suspension resulted in a decline in mine production and exports of rare-earth compounds.”
Despite the excess supply, exploration has continued in the United States, as well as in several other countries — especially where bastnäsite and monazite deposits are found. Geochemical exploration is the main method of REE exploration. Portable XRF is a very useful tool to qualitatively and quantitatively evaluate REE projects in real time in the field. Portable XRF instruments can provide real-time, on-site assays of REEs and other elements in any type of geological samples, including elements associated with REE-bearing minerals. By using the concentrations from these elements, it is possible to infer concentrations of heavy REEs (HREEs) that are commonly associated with host minerals.
Ores of rare earth elements are mineralogically and chemically complex and commonly radioactive. Currently, REEs are extracted from the two mined minerals I mentioned: bastnasite and monazite. However, sometimes rare earth elements are found where least expected. Rare earth manganese nodules have been found beneath the Atlantic Ocean. A Popular Science article reported that “Last summer the UN’s International Seabed Authority issued the first deep sea exploration permits, allowing companies to start actively looking for places to mine nodules and other sources of rare earth elements from the ocean floor.” Because of this find, a three-year research project involving 25 European research institutions will focus on analyzing the impact of deep sea mining on the seafloor environment.
What do you think about mining the seafloor to aid energy efficiency? Comment below.