Mobile phones contain numerous metals, including expensive ones. The most important are: copper, nickel, silver, gold, platinum group metals, cobalt, lithium, lead, tin, zinc, rare earth metals, gallium, indium, iron, chromium, niobium, tantalum, titanium.
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China's position as the world's dominant producer and supplier of rare earths (97% of total output)。
一說中國稀土產量占全球總產量的 70% 以上,甚至高達97%。
稀土在華的貯藏量 為地球的40% (?)
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Rare earths aren’t particularly rare. Cerium, the most abundant, is more common in the Earth’s crust than copper. All other rare-earth elements, besides promethium, can be found more widely than silver, gold, or platinum, according to the U.S. Geological Survey. However, concentrated and economic deposits are scarce, and production is dominated by a handful of countries. China is the biggest by far, accounting for almost 70% of global production and 40% of the world’s reserves, USGS data show.
Rare But Everywhere
Rare-earth elements have widespread uses in defense, energy and technology
Element
Symbol
Characteristics
Scandium
Sc
Light alloys for the aerospace industry, as a radioactive tracer, and in lamps.
Lanthanum
La
High refractive index glass, camera lenses and catalysts.
Cerium
Ce
Used to give a yellow color to glass, as a catalyst, as a polishing powder, and to make flints.
Praseodymium
Pr
Lasers, arc lighting, magnets, flint steel, and as a glass colorant, in high-strength metals found in aircraft engines and in flint for starting fires.
Neodymium
Nd
Some of the strongest permanent magnets available; used to give violet color to glass and ceramics, in lasers, capacitors, and electric motorsdiscs.
Promethium
Pm
The only naturally radioactive rare earth element. Used in luminous paint and nuclear batteries.
Samarium
Sm
Lasers, magnets, masers, nuclear reactor control rods.
Europium
Eu
Used to prepare red and blue phosphors (marks on Euro notes that prev ent counterfeiting,) in lasers, in fluorescent.
Gadolinium
Gd
Lasers, x-ray tubes, computer memory, high refractive index glass.
Terbium
Tb
Used in green phosphors, magnets, lasers, fluorescent lamps, magnetostrictive alloys, and sonar systems.
Ytrrium
Y
Used in yttrium aluminium garnet (YAG) lasers, as a red phosphor, in superconductors, in fluorescent tubes, in LEDs, and as a cancer treatment.
Dysprosium
Dy
Permanent rare earth magnets; Lasers and commercial lighting; hard computer discs and other electronics; nuclear reactors and modern, energy-efficient vehicles
Holmium
Ho
Use in lasers, magnets, and calibration of spectrophotometers can be used in nuclear control rods and microwave equipment
Erbium
Er
Vanadium steel, infrared lasers, and fiberoptics lasers, including some used for medical purposes.
Thulium
Tm
One of the least abundant rare earths. Used in lasers, metal halide lamps, and portable x-ray machines.
Ytterbium
Yb
Health care applications, including in certain cancer treatments; stainless steel and for monitoring effects of earthquakes, explosions.
Lutetium
Lu
Positron emission tomography (PET) scans, high refractive index glass, catalysts, and LEDs.
Rare earths aren’t particularly rare. Cerium, the most abundant, is more common in the Earth’s crust than copper. All other rare-earth elements, besides promethium, can be found more widely than silver, gold, or platinum, according to the U.S. Geological Survey. However, concentrated and economic deposits are scarce, and production is dominated by a handful of countries. China is the biggest by far, accounting for almost 70% of global production and 40% of the world’s reserves, USGS data show.
China’s rare earth market is dominated by a handful of producers including China Northern Rare Earth Group, Minmetals Rare Earth Co., Xiamen Tungsten Co. and Chinalco Rare Earth & Metals Co. The nation has form in using the elements to make a political point. It blocked exports to Japan after a maritime dispute in 2010, although the consequent spike in prices saw a flurry of activity to secure supplies elsewhere, which would be the risk again if Beijing follows through with its threat of retaliation.
China Northern rose as much as 9.3% in Shanghai, while Lynas Corp., the biggest producer of rare earth products outside China, added as much as 16% in Sydney. Hong Kong-listed China Rare Earth Holdings Ltd. spiked as much as 41% and has doubled in value in May.
China’s stranglehold is so strong that the U.S. joined with other nations earlier this decade in a World Trade Organization case to force the nation to export more amid a global shortage. The WTO ruled in favor of America, while prices eventually slumped as manufacturers turned to alternatives.
In December 2017, U.S. President Donald Trump signed an executive order to reduce the country’s dependence on external sources of critical minerals, including rare earths, which was aimed at reducing U.S. vulnerability to supply disruptions.