technical report on the nechalacho deposit, thor lake project ...

• loparite and eudialyte in alkaline intrusives (Kola Peninsula, Russia; Dubbo, Australia)
• Pegmatites, hydrothermal quartz and fluorite veins (Northern Territories, Australia;
Karonge, Burundi; Naboomspruit, South Africa)
Other generic types which may contain rare earths are:
• Phosphates (Phosphoria Formation, western USA),
• Uranium deposits in sandstone and black shales (Wheeler River, Alberta; Williston
Basin, Saskatchewan),
• Mylonites in limestones (Nam-Nam-Xe, Vietnam),
• Scheelite skarns (Ingichke, Uzbekistan),
• Nickel deposits (Sudbury Basin, Ontario).
By far the most important of current sources are the Bayan Obo iron rare earth deposits near
Baotou, Inner Mongolia, the bastnaesite deposits in Sichuan, China and the ionic clay deposits
in southern China. China is the dominant source of all rare earth oxides, accounting for
approximately 97% of world production in 2009. Light rare earths are primarily produced in
northern China (Inner Mongolia) and south-western China (Sichuan). The heavy rare earths are
primarily produced in southern China (Guangdong), from ionic clays.
There are distinct differences in the elemental composition of various rare earth sources, as
illustrated in Table 18-18.
As a consequence of the mix of the individual elements within a raw material source, the
distribution of supply of the individual elements does not match the distribution of demand for
the elements. The mixed composition of rare earth minerals necessitates the production of all
of the elements within a given ore source. Such production does not necessarily equal the
demand for the individual oxides, leaving some in excess supply and others in deficit. Overall
production of rare earths on an oxide basis is therefore typically greater than the sum of
demand for the individual elements in any given year.
Total supply of rare earth oxides for 2008 was estimated at between 121,600 tonnes and
127,100 tonnes, as illustrated in Table 18-19.
Technical Report 43-101 – March 13, 2011 Page 18-74
Prepared by Avalon Rare Metals Inc.