At 0.5% of the RE suite and prices (FOB) near enough to $1000 it contributes $5 to the 'basket' price. More than the (roughly) 50% Ce at $6 or 25% La at $15 (if they can get it). There is a concern over long term demand (eg the shortage/surplus plot Aus has posted several times). Two factors may mitigate this. - Will the world go straight to LEDs from filament bulbs or will it be via cheaper flouro technologies? - I've seen research in the use of Europium to give LEDs a better spectrum.
Info from these sources: http://www.frontierrareearths.com/rare-earths/rare-earth-prices
