That was a marked 30.8% pullback from December 2018, the researcher said.

By value, China exported US$36.6 million worth of REOs in January 2019, which marked a year-over-year increase of 23.6% compared with the value exported in January 2018, and a month-over-month decrease of 17.9% versus the value exported in December 2018.

Overall, China's rare earth exports commanded an average price of $9.75/kg in January 2019 - an 18.5% increase over the month prior and a 28% increase over January 2018.

Beijing has been tightening environmental policy and has clamped down on illegal mining activity, taking total Chinese REO production lower. The reported inventory levels in China had declined steadily over the past three years, which signalled the rampant overproduction in China of the magnet rare earths dysprosium, neodymium, praseodymium and ytterbium had essentially vanished.

"This signals overproduction is now under control and it is laying the groundwork for higher prices going forward this year into 2019," founding director Ryan Castilloux told Mining Journal in a recent interview.

The West is looking to diversify its technology-focused supply chains from Chinese dominance following a 2010 Chinese clampdown on export quotas that sent REO prices soaring to all-time highs. To this end, the US has designated several REOs among its list of 35 minerals deemed critical to its economic and national security.