To clarify the Ni in pounds bit: it all depends on where you get your PON/NP info from and in what terms you want to think about the price. If it's quoted in USD/tonne (eg: direct from LME) and you're happy to think in terms of price per tonne, then there's no need for any conversion from pounds. Only need to consider the AUD:USD Fx rate, in order to relate it back to AUD/tonne.
Many punters get their (New York) cash spot Ni prices from ***** (link) which quotes in USD/lb. Much of the international community thinks in terms of USD/lb. That's when conversion from pounds to metric tonnes (2,204.63 conversion factor, or 2,204/2,205 rounded) comes into play, if you're wanting to think in terms of tonnes. Again, the AUD:USD Fx rate still needs to be considered, in order to relate price back to AUD currency terms (this time in AUD/lb.).
Personally, my quick-and-dirty default is to think in terms of price/lb. I visually check the daily spot data on *****, so all I need to do is apply the current Fx rate to convert into AUD/lb. To complicate things, however, my nightly data feed downloads directly from the LME, which is in USD/tonne, which means I also need to know the equivalent in AUD/tonne. Do it for long enough and thinking in either AUD/lb. or AUD/tonne becomes second nature in which it's not hard to flick between the two, depending on what report you're reading or how the Ni company you're analysing/researching presents their info. Becoming fluent in both will help greatly, imo, because most Ni companies report in terms of one or other or both.
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