Right now they are establishing volume, and refining their estimate of the grade in each volume identified,

BTW, how are they establishing "volume"?

They have to establish a volume that contains gold in it which is probably mineable using some method or other.

Here's an example. The city of Montreal has an area of 365 sq.km. Bedrock starts maybe 100m down? and let's assume the bedrock goes down for 10.1km before you hit mantle. Therefore, Montreal sits on 36,500 square kilometres of rock! Wow, at 2 grams of gold per tonne, they're rich!

Except there's no such thing as 2 grams per tonne of gold in the rock under Montreal (that we know of). Similarly, we haven't seen 2 grams per tonne in GNH's assays, except over rare narrow intervals here and there. Most of the rock in these cores seems to not have gold in it, according to the assays. So really, GNH is only establishing volume of rock that has no gold.

Then again, maybe I've missed something? Can someone post some holes released in the past that show decent intervals of decent grade gold?