World-Class Rare Earth Deposits
Source: Rare Earth Investing News, Leia Michele Toovey (9/28/10)
"Explorers are racing to discover and develop the world's next REE mines."
From the initial discovery of the REEs in the late 1700s through the mid-1950s, a few of the REEs were produced in modest amounts from monazite-bearing placers and veins, from pegmatite's and carbonatites, and as minor byproducts of uranium and niobium extraction. During this time, the middle and heavy REEs generally were available in pure form only in sub-kilogram quantities and were chiefly chemical curiosities.
To make exploration for REEs profitable, deposits need to be discovered in areas where they occur in dense concentration, and there are very few areas in North America where the REEs are found in abundance. The number of workable REE deposits, already severely limited by the geochemical properties of the elements, has in recent years also been affected by environmental and regulatory factors. Monazite, the single most common rare earth mineral, generally contains elevated levels of thorium. Thorium is accompanied by highly radioactive intermediate daughter products, particularly radium, which can accumulate during processing. Concern about radioactivity hazards has now largely eliminated monazite as a significant source of REEs and focused attention on those few deposits where the REE occur in other, low-Th minerals, particularly bastnäsite.
Approximately 95% of the world's supply of REEs come from China. With China using nearly two-thirds of what it produces, it's naturally keen to protect its own interests. The country is stockpiling its supplies and continuing to reduce annual exports of rare earths. The real concern is—within a few years, China may decide to keep everything it produces. Exploration companies around the world are now in a race to discover and develop the world's next REE mines.