isolated via a countercurrent liquid-liquid extraction process. As a result, cerium is overproduced by about 50,000 tons per year and must be stored at a real cost (Gschneidner, 2011). As expected, the rare earth industry would welcome new large cerium applications, but so, too, would all other users of rare earth elements because a balanced cerium market would significantly reduce the prices of the other rare earth elements.
Shinar observed that rare earths can be separated into three categories—surplus, balanced, and tight. Only neodymium, terbium, and dysprosium fall into the tight-supply category. Other than cerium and holmium, which is actually one of the rarest of rare earth metals, supplies and demands for the other rare earths are well balanced. It is also important, he added, to remember that the proven reserves of rare earths are growing rapidly.
The solution to the expectation that supplies will become tight as a result of China’s new policies is to increase mining, Shinar stated. That, in fact, is happening because MolyCorp is investing in reopening and expanding its operations at Mountain Pass. Workforce training also will be important.
One lesser-known fact about the critical elements is that the supply of ITO, the quintessential transparent conducting material, is totally dependent on zinc production, and the demand for zinc is not expected to grow much in the future because of macroeconomic factors in China, Canada, Korea, and Japan. Annual production of indium is approximately 900 tons, with primary production of 600 tons and recycling and stockpiles providing the rest. Recycling occurs primarily through removing the thin ITO layer coated on glass used in LCD monitors, flat-screen televisions, and other display devices.
Demand for ITO, which accounts for 85 percent of all indium demand, is expected to grow by 15 percent per year over the next 3 years. Emerging uses are in copper-indium-gallium-selenium solar cells, electrode-less lamps, mercury alloy replacements, and nuclear reactor control rods. Though indium prices are much the same as they were 5 years ago, the price has spiked thanks to China’s recent crackdown on small lead and zinc refiners amid environmental concerns.
Shifting his focus from the general to the specific, Shinar spoke next about europium red phosphors, particularly europium-doped yttrium oxide, or yttria. Europium accounts for about 0.3 percent of mined rare earth metals, and the demand of about 400 tons of oxide per year is balanced by supply. Yttrium represents 6 percent of mined rare earths, and its supply and demand are balanced as well, at about 8.5 kilotons of oxide per year.
“The main use of red phosphors is as the R in RGB,” said Shinar. He explained that ytrium doped with 4 to 6.5 percent europium produces an intense red phosphorescence at 611 nanometers (nm) (Sylvania, 2010). “Even though RGB monitors and televisions are soon going to be found only in museums, red phosphors are still used extensively in compact fluorescent lamps (CFLs). And hot on the heels of CFLs are white LEDs for solid-state lighting.” But even though the demand for europium and yttrium will continue to grow, proven reserves of these metals are outpacing expected increases in demand.
Erbium accounts for about 0.5 percent of mined rare earths, and the demand of 700 tons of oxide per year is balanced with supply. Erbium is used as a colorant and as a stabilizer for zirconium in jewelry, but its most critical use is in the repeaters used in optical fiber networks that operate with a carrier wavelength of 1.5 microns. These repeaters, which are optically pumped lasers, are incorporated into fiber networks every few kilometers to boost the optical signal. Shinar noted the demand for these lasers may slowly wane as wireless communications steadily grow.
A niche application for rare earths is in neodymium, erbium, and holmium-doped YAG lasers. YAG lasers, which are very robust, efficient solid-state lasers, are staples in optical electronic labs and are used extensively in spectroscopy and ultrafast spectroscopy. Holmium-doped YAG lasers also are used extensively by urologists in laser lithotripsy. Though these are niche applications, they are critical ones nonetheless. Of the three rare earths used in these lasers, only neodymium is in tight supply. Though it represents 16 percent of mined rare earth oxides, it is used extensively in the neodymium-iron-boron magnets incorporated in wind turbines. Of the 23 kilotons of neodymium oxides mined, 2.8 kilotons go into wind turbines alone. Holmium represents about 0.1 percent of mined rare earth oxides, and its supply of 100 tons of oxide per year exceeds demand.
Indium demand is expected to grow rapidly with the development of what are called indium group II-V devices for use in the street lighting market. These devices, which are based on new technology for growing high-quality indium-doped gallium nitride, are superior replacements for fluorescent and high-pressure sodium lamps in overhanging street lights. The City of Anchorage, Alaska, estimates that replacing 25 percent of its streetlights with these new lamps will reduce energy costs by 50 percent and save the city some $360,000 per year. In addition, maintenance costs should drop given that these bulbs have an expected lifetime of 100,000 hours—over 11 years—compared with 5,000 hours for fluorescent and high-pressure sodium lamps. Perhaps more importantly, the new lamps improve visibility dramatically because of superior color rendering.
Indium is also used in ITO photovoltaic devices, displays, and SSL industries. Shinar focused his remarks on organic LEDs (OLEDs), which first appeared in a commercial product in 1998 and is now making major inroads in display devices. In 2007, Sony introduced an 11-inch OLED television, but at a cost of $2,500 it was not a big selling item. Since then, at least one company announced it was introducing a much bigger OLED television, but it has yet to appear