geologist or mining engineer help please, page-92

Look, when talking about % please note that the company is talking about "Material" not "ore", in other words the content of the drill hole, Quartz, clay, and IO, seperation and washing is required, almost all the alumina is contained in the clay, and the vast bulk of the silica is seperate rock/sands/pebbles from the OI rock/sand/pebbles and can be screened out, we can talk on this point forever so best we leave it until the study is released.
Just realise the drfference between ORE and Material, you talk as if the IO has a TRAPPED [ie in one rock] 25% silica component, it is not so.
cheers