A NPV of $188M for 18 years mean they estimate a net profit of $10M USD per year (which was what I got from my calculation) with 1.5% of laterite (saprolite) ore price but that means they need to find 36Mt of 1.5% saprolite deposit (which they haven't entirely JORC), their low grade 1% laterite (limonite) isn't a viable operation (as they have also indicated in their PFS), currently cost more to mine.