Hi SnicketI don't know much about rocks and am not a geo so take...

Hi Snicket
I don't know much about rocks and am not a geo so take the below for what I intend it to be and for what it is worth having regard to my lack of qualifications in this area.

I did a little research on this because I thought it was a good question!

From my research pisolitic gravels seem relevant to the the possibility of a channel Ore deposit ie the source of the gravel and is used in the context of mostly Channel iron deposits hence sometimes channel iron deposits are referred to as Pisolitic Iron (say that when you have had a few beers or shots). Pisolites are nodules of hematite, limonite-goethite with some clay, sand and silt mix in them. The relevance seems to be that the fact that they have located pisolitic gravel means it may have come from a channel deposits which are a major source of very cheap, high grade IO found ususally in the Pilbara and Muchison areas of WA. The pisolitic gravel erodes from the source and washes down into river beds known as palaeochannels over millions of years. The fact that they suspect a palaeochannel is important in economic terms because palaeochannels can host very lucrative ore deposits themselves including precious metals, uranium and importantly for shareholders iron ore and others that are not relevant to the burning question do we have ORE in HAW and is it of the Iron variety with little contaminants?

I hope this helps because your question helped me by turning my attention to it. If I am wrong please forgive me because I am flying blind. This is not my area.

Cheers