First, Niobium & REE's were not used much back when this study was done and these materials were mostly not worth mining at the levels it was going for on the market. Simple supply & demand thing. The cost of extraction would have far exceeded the profit. But that has all changed now.
We are now in the Computer Age Where mass quantities of REE's are needed for your Laptops, Flat Screen TV's, PDA's, IPOD's, Cell Phones, Video Games etc... and Steel production has changed Drastically where we are demanding Higher Quality Steel products resistant to corrosion and much stronger than they produced in the past. With the economy the way it is, this will continue to change and Niobium is going to be needed more and more. Prices for all these materials will continue to rise with the continued rise in demand.
Also, the main purpose of the Gulf study was exploratory.
Cheers,
TheGoodlifeGeo