Avalon and Cheetah want to work together at the Nechalacho project near Yellowknife.
Neodymium Mining News
This will mean Geoscience Australia and the United States Geological Survey (USGS) will work closely on exploration, extraction, processing and research and development.
The shutdown of the controversial plant could see the Australian rare earths producer take a A$16 million hit.
Some urban mining already takes place in the EU but it involves melting devices together in a furnace and removing the most valuable metals.
There is no single rare earth element market. Instead, the rare earth universe is made up of four or five distinct "critical rare earth" markets that should be the focus for investors today.