Commodity Classification

 In chemistry, metals that oxidize or corrode easily are referred to as "base metals." These industrial metals include copper (Cu on the periodic table), nickel (Ni), aluminum (Al), zinc (Zn), lead (Pb), tin (Sn) and iron (Fe)/steel (an alloy of iron and carbon). Base metals are generally plentiful and are used in a variety of commercial and industrial applications, such as copper plumbing, aluminum cans and the steel used in automobile production. Because of their abundance, prices for base metals are far below those of both precious and rare-earth metals, and prices respond to changes in demand for the products for which the metals are used. 
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Precious metals are naturally occurring metallic chemical elements that have a high luster and melting point, are softer and more ductile than other metals and are less reactive than most elements.  include silver (Ag), gold (Au), platinum (Pt) and palladium (Pd). Because of their scarcity, precious metals are valuable – much more so than the base metals. Precious metals are used for jewelry, art, coins, dental work, medical devices, electronics, and investment/holding purposes. (Add some sparkle to your portfolio by getting in on this classic commodity; check out Getting Into The Gold Market source: http://www.investopedia.com/articles/stocks/11/how-to-invest-in-the-periodic-table.asp

Element
Common Uses
Non-Lanthanides
Scandium
Aerospace components, mercury-vapor lamps
Yttrium
Lasers, microwave filters, high-temperature superconductors
Light Rare Earth Elements (LREE)

Lanthanum
Camera lenses, a catalytic cracking catalyst for refining oil, high refractive index glass, battery electrodes
Cerium
Glass and ceramics, polishing powder, chemical oxidizing agent
Praseodymium
Rare earth magnets, lasers, carbon arc lighting
Neodymium
Rare earth magnets, lasers
Promethium
Nuclear batteries
Samarium
Rare earth magnets, lasers, masers
Heavy Rare Earth Elements (HREE)

Europium
Lasers, mercury vapor lamps
Gadolinium
Rare earth magnets, lasers, x-ray tubes, MRI, computer memory
Terbium
Lasers, fluorescent lamps
Dysprosium
Rare earth magnets, lasers
Holmium
Lasers
Erbium
Lasers, vanadium steel
Thulium
x-ray machines
Ytterbium
Lasers
Lutetium
PET scanners, high refractive glass

source: http://www.investopedia.com/articles/stocks/11/understanding-rare-earth-metals.asp

Alloys http://practicalmaintenance.net/wp-content/uploads/Metals-Classification.jpg

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