The intersection I'm referring to is what has been dubbed 'The Glory Hole'. A 450g/t spike over 1 metre from and back to a background around 9g/t and from there dropping to 6g/t and lower.
Gold typically shows a very high nugget effect that means that grade continuity in any direction has a very short (often centimetres) range. Compound this with the fact that LDM is a shear zone and you have the added complication that shearing dissects and smears the grades that you do see - step out of the individual shear plane and your grade is gone.
Another thing to consider is what you're analysing for - 450g/t sounds fantastic, but it's only 450 parts per million within the sample. Consider that half of that 1 metre of core weighed in excess of 2kg and would have been crushed, ground and split down to something around 30g prior to the actual analysis and you open all kinds of possibilities for sample bias; that 450ppm could be just one grain of gold that ended up in the sample instead of going to the waste pile.... A company that sees such a spike out of the normal statistical range would run duplicate or triplicate samples to verify the grade and take an average of the results, and also cut the grade back to the limit of the statistical outlier range or variogram sill level to bring the results into a more meaningful range and stop the kind of 'gold fever' that seems to grip some investors.
When you take the likely range of the gold spike (if it is correct) and allow for the potential enclosed volume of rock, the fridge analogy is quite generous.... The rest of the shear zone that you will have to extract lies somewhere between 1g/t and 9g/t based on the assays to date if we accept them as viable (which they are not).
An average of 9g/t is just about at the limits of economic viability for an underground operation these days - mining within a shear zone in such poor ground (witness the bracing in the whinze) makes that extraction problematic when you start large-scale blasting to extract large (say 50m strike and 25m plane of shear) panels via long-holing. The level of ground support will have to be high to maintain the working areas (you'd be amazed how much ground away from the blast point can be shaken up by large blasts) and to prevent collapse and dilution, all of which will push up your costs markedly and could render the whole project uneconomic. If that's the case then this single-level drift is all you will get.
As for big tonnage porphyry bodies; you don't have one yet, it's all just wishful thinking; that may go down a storm on MP, but doesn't even register on the radar of any serious mining company who are only interested in verified tonnage and grade. And as for the photos - blurred, no scale or context (certainly that last batch); they don't do nearly as much for me as they do for you.
