Ann: Quarterly Activities Report, page-10

Don't confuse hard rock spodumene deposits in Australia with sedimentary clay deposits in North America. Australian spodumene is an order of magnitude higher in concentration as you point out but you have to mine it including removing overburden and crushing it. Clay deposits in the US can be dug up with a back hoe. The grade may be lower but the mining cost is a fraction of what it is in Australia. US deposits also have all the infrastructure on tap including railways, labour force, gas, electricity and paved four-lane highways to Elon Musk's factory. Outback WA has none of this. In the end however, there will be a market for both. DYOR.