re: Ann: Significant hematite discovery confi... From a Hartley's report on Mid-West IO hopefuls, I found the following details for "desirable contaminants and grade levels" for hematite ore:
Fe% >55
SiO2% <5
P% <0.1
S% <0.05
Al2O3% <2
LOI% 7-10
So, whilst the numbers are a bit all over the shop, you'd have to say that, on average, the results are pretty much on the money.