Mineral Resources. Rare Earth Elements (REEs) Non-metallic resources Sand and gravel Salt Diamonds

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1 Mineral Resources Non-metallic resources Sand and gravel Salt Diamonds Metallic resources Ore forming processes Copper, Gold and Molybdenum Rare Earth Metals Next time: Mineral Research Projects! Rare Earths: Rarely concentrated deposits Rare Earth Elements (REEs) Atomic No. Symbol Concentration (ppm) Element 39 Y 33 Yttrium 57 La 30 Lanthanum 58 Ce 60 Cerium 59 Pr 8.2 Praseodymium 60 Nd 28 Neodymium 61 Pm 0 Promethium 62 Sm 6 Samarium 63 Eu 1.2 Europium 64 Gd 5.4 Gadolinium 65 Tb 0.9 Terbium 66 Dy 3 Dysprosium 67 Ho 1.2 Holmium 68 Er 2.8 Erbium 69 Tm 0.5 Thulium 70 Yb 3 Ytterbium 71 Lu 0.5 Lutetium Discovered 1700s Difficult to isolate Soft, lustrous metals Ductile Highly reactive All trivalent ( 3+ ) 1

2 Rare Earth Elements (REEs) Atomic No. Symbol Concentration (ppm) Element 39 Y 33 Yttrium 57 La 30 Lanthanum 58 Ce 60 Cerium 59 Pr 8.2 Praseodymium 60 Nd 28 Neodymium 61 Pm 0 Promethium 62 Sm 6 Samarium 63 Eu 1.2 Europium 64 Gd 5.4 Gadolinium 65 Tb 0.9 Terbium 66 Dy 3 Dysprosium 67 Ho 1.2 Holmium 68 Er 2.8 Erbium 69 Tm 0.5 Thulium 70 Yb 3 Ytterbium 71 Lu 0.5 Lutetium Abundance - Even atomic numbers are more cosmically abundant Rare Earth Elements (REEs) Atomic No. Symbol Concentration (ppm) Element 39 Y 33 Yttrium 57 La 30 Lanthanum 58 Ce 60 Cerium 59 Pr 8.2 Praseodymium 60 Nd 28 Neodymium 61 Pm 0 Promethium 62 Sm 6 Samarium 63 Eu 1.2 Europium 64 Gd 5.4 Gadolinium 65 Tb 0.9 Terbium 66 Dy 3 Dysprosium 67 Ho 1.2 Holmium 68 Er 2.8 Erbium 69 Tm 0.5 Thulium 70 Yb 3 Ytterbium 71 Lu 0.5 Lutetium Abundance - LREE (light REE): less compatible due to larger ionic radius, therefore more concentrated in REE deposits - HREE: heavy rare earth elements Abundance of elements in upper continental crust 2

3 REE Formations Deposits -Mountain Pass, California -Oka & St. Honore, Quebec -Jacupiranga, Brazil -Phalaborwa, South Africa -Baiyun Obo deposit, China (45% world production) -Pea Ridge, Missouri (production from tailings) -Two deposits in China (14% of world production) -Mount Weld, Australia REE Formations: Carbonatite rocks Very rare, igneous rocks, 50% carbonate rock Formation theories - very low temp. partial melts in the mantle, melt differentiation - liquid immiscibility between carbonate and silicate melt - extreme crystal fractionation May contain REE, P, niobium, uranium, thorium, Cu, Fe, titanium and other rare or incompatible elements Deposits -Mountain Pass, California -Oka & St. Honore, Quebec -Jacupiranga, Brazil -Phalaborwa, South Africa carbonatites line volcano's flanks like snowballs East African Rift, Tanzania Only currently erupting carbonatite REE Formations: Iron-REE deposits Hydrothermal activity in carbonatites and surrounding rocks forms iron-oxide deposits with REE Deposits -Baiyun Obo deposit, Inner Mongolia (45% world production) -Pea Ridge, Missouri (production from tailings) 3

4 REE Formations: Lateritic clay Laterite: weathered parent rock in hot, tropical environments -Wet season leaches ions from parent rock -Dry season brings ions close to surface where they precipitate Laterites form REE crust over alkaline igenous rocks (such as granite, carbonatite) Deposits -Longnan Deposit, Southern China -Xunwu Deposit Southern China -Mount Weld, Australia 14% of world production Bayan Obo deposit Inner Mongolia, China 45% world production 70% of worlds known reserves Discovered in 1927 as iron mine -REE discovered in 1936 Reserves of REE 89 million tons -Grade: 3-5% Bayan Obo deposit Inner Mongolia, China Largest fluorite deposit (CaF 2 ) Between 555 to 395 Ma Minerals - bastnaesite (Ce,La,Nd)(CO 3 )F - monazite (Ce,La,Nd)PO 4 Top: Microfolded banded ore of lenticular layers of monazite (m), granular hematite (he), fluorite (fl) Bottom: Banded ore of granular apatite (ap), granular hematite (he), monazite (m) (modified from Chao et al.,1997) 4

5 Mountain Pass Mine Reserves: 50 Mt Environmental problems with main wastewater pipeline REE separation plant closed in 2002 Active mining in mid-60s for Europium in color televisions US REE Deposits 5

6 Mountain Pass Mine 1. Precambrian host rock: gneisses, schists 2. Intruded by granite 3. Cut by pegmatitic dikes 4. Metamorphosed 5. Intrusion of carbonatite complex (1.4 Byr ago) -60% carbonate -20% sulfate -10% bastnaesite (LnFCO 3 ) -10% silicate (quartz) Enriched in LREE Mountain Pass Mine 50% Cerium -catalytic converters -sulfur dioxide pollution control from oil refineries -diesel fuel additive for more complete combustion -cerium polish very common for: disk drives & micro-processors mirrors eyeglasses -can de-colorize glass -TV glass to shield UV radiation emitted from CRT Mountain Pass Mine 34% Lanthanum 1. Hydrogen storage in NiMH rechargeable batteries -provides longer battery life -25 lbs per Prius battery! 2. catalyst to create fuel -eliminated need for leaded gasoline -catalysts promotes energy efficient petroleum cracking 3. modifying glass crystal structure and refractive index -high-tech digital cameras, video cameras 4. energy providing alloys in fuel cells and batteries - alloys can store H at many times their own volume 5. X-ray films and certain lasers to help reduce the dose of radiation to patients by up to 75% 6

7 Mountain Pass Mine 11% Neodymium: 1. Neodymium-Iron-Boron forms a strong permanent magnet that maximizes power/cost ratio in electric motors -Allowed revolution in the miniaturization of electronics -Air bags, anti-lock brakes -Hybrid car electric motor (2.2 lbs per Prius) 2. Strong absorption band centered at 580-nm -enhances picture brightness in cathode ray tube glass -Coloring pigments in glass and ceramic -Surgical blue-light lasers for illumination Other REE elements used for magnets: Samarium, Gadolinium, Dysprosium or Praseodymium Mountain Pass Mine 4% Praseodymium: 1. filters certain wavelengths of light -coloring agent in glass and ceramics -photographic filters -welders glasses -Alloy component of permanent magnets to make smaller and lighter motors Mountain Pass Mine 0.2% Yttrium -Improves efficiency of fuels with oxygen sensors composed of Yttrium based ceramic materials -Microwave communication for defense and satellites 7

8 Mountain Pass Mine 0.1% Europium -excited by UV radiation or absorption of electrons to emit photons -only element used as red phosphor in flat screen televisions and computer screens -fluorescent light bulbs -medical tag within the body -$250 to $1,700/kg Other REE elements used for fluorescent lamps: Yttrium, Lanthanum, Cerium, Gadolinium, Terbium REE usage REE deposits US versus foreign deposits Atomic No. Symbol Concentration (ppm) Element 39 Y 33 Yttrium 57 La 30 Lanthanum 58 Ce 60 Cerium 59 Pr 8.2 Praseodymium 60 Nd 28 Neodymium 61 Pm 0 Promethium 62 Sm 6 Samarium 63 Eu 1.2 Europium 64 Gd 5.4 Gadolinium 65 Tb 0.9 Terbium 66 Dy 3 Dysprosium 67 Ho 1.2 Holmium 68 Er 2.8 Erbium 69 Tm 0.5 Thulium 70 Yb 3 Ytterbium 71 Lu 0.5 Lutetium 8

9 Mining concerns: processing Radioactivity from uranium and/or thorium in waste rock - monazite: 4-10% radioactive thorium -baestnasite: <1000 ppm thorium Thorium is only weakly radioactive but decays to radium -decay series:! Thorium 227! Radium 223! Radon 219! Polonium 215! 19 days 11 days 1.8 msec US consumes 10t/yr thorium - much less than production Mining concerns: processing REE processing outside of China -La Rochelle, France -Freeport, Texas closed -Protests prevent processing in W. Australia, Protests of highly radioactive waste prevent processing by Japanese Mitsubishi Chemical in Malaysia, Chemical processing at Mountain Pass mine suspended in 1998 after a spill with radioactive material -Australian, Lynas, building $230 million rare earth refinery in Malaysia -Mount Weld, Australia rare earth deposit -Ability to process 1/3 of world demand -Projected $1.7 billion/yr in exports -Thorium waste will be diluted (to 0.05%) in limestone and turned into concrete for artificial reefs and seawalls Mining concerns: processing 9

10 Mining concerns Possible water contamination from spillage or leakage of acids used to leach and process ore Dust from mining activities Acid or metal-contaminated drainage from pyrite-rich carbonatites -though abundant carbonate minerals generally neutralize acids Supply of rare earths Rare Earth Bubble Global production around 100,000 tons per year -production cut by 2/3 in production cut another 1/3 in 2011 Demand projected at 200,000 tons by 2020 World reserves estimated at 150 million tons New mines take 5-10 years to come online Global manufacturers moving to China Supply of rare earths 10

11 Supply of rare earths Supply of rare earths: start up time Supply of rare earths 11

12 Supply of rare earths Supply of rare earths Flow of Rare Earth materials (for NdFeB magnets for PHEVs) 12

13 Flow of Rare Earth materials (for NdFeB magnets for PHEVs) Global requirements for Rare Earth materials outside China are expected to grow dramatically, fueled primarily by continued development and deployment of emerging Green Energy technologies such as Hybrid Vehicles, PHEVs, Energy Efficient Lighting and Wind Power Global shortages of these materials may be seen as early as 2010, with shortages becoming severe by Supply of rare earths Global requirements for Rare Earth materials outside China are expected to grow dramatically, fueled primarily by continued development and deployment of emerging Green Energy technologies such as Hybrid Vehicles, PHEVs, Energy Efficient Lighting and Wind Power Global shortages of these materials may be seen as early as 2010, with shortages becoming severe by