Don't have much of an issue with the raw numbers used for the niobium/tantalum, but would add mutlpliers/divisors for the certainty factors...
The values for REE are improbably high, I think, both in that they will tend to be more unevenly distributed rather than uniform in the ores, and in that they have processing cost factors that are hard to quantify variables relative to the values left post processing. Niobium having a 90% recovery factor doesn't mean the others will, too. Need either to define the separations processes and costs, or reduce the values on REE to ore values as "bulk REE concentrates" rather than end product values, which is also true of the niobium/tantalum numbers.
Otherwise, I thought your prior charts had market multiplier/divisor factors, too... so that the costs of extraction and processing and capital costs were considered in a "present value" sense...
A wag of 10% of residual resource value from a compliant resource is a useful, if imprecise, market averaged valuation tool. Current market conditions impose a larger source of variation, now, so apply some adjustment to that...
The new zones aren't close to compliant... so a larger discount to value for that will be needed until we're to the point of having proved that value...
I think you can be ultra conservative by using only the niobium and tantalum values, only in Zone D... knowing Zone D is open at depth, and has higher values deeper... and still have LOTS of room for future upside without applying values for any of the other minerals, or any of the other zones.
Use $6 billion as a known low side value of minerals present, and 850 million shares authorized... that gives you around $7 a share in mineral value, but that is a post extraction value in a pre-extraction reality... so divide that by half for extraction costs, to $3.50, and divide that by ten to get a standard market NPV $0.35... then discount that by the market we have... and it looks to me like a hyper conservative $0.125 NPV... RIGHT NOW... after having covered costs TWICE, and then discounting to the present market... all with still having NOT valued REE or other zones at anything.
I think getting zone D compliant removes the need to double cover costs... getting you to a NPV range of $0.35 to $0.70, still without having addressed REE or other zones...
The meaning of not including values for REE ? You probably do need to see both a compliant REE estimate on quantities, and some mineralogical test data that shows what the REE are likely to give as an commercially viable % in extraction rate in a fully costed process that includes them. I DO expect that the REE values present will be less than yours suggests, but should be enough that they might provide a return sufficient to cover the operating costs... which is a HUGE deal. I also expect operating costs to be lower than many others might expect, based on the unitary nature of the deposit being proven... which would mean that my overly conservative calculation above would end up covering the mining and processing costs three times over instead of only twice...
I expect compliance on the REE present, when paired with mineralogical information that allows valuing them properly... could add significantly to my numbers...
If the REE values WILL cover the costs... that gives you a big factor as a multiplier... maybe giving you a still discounted value in the range of $3.50 a share... before valuing anything other than zone D ??? The multiple coverage of costs gives you LOTS of room to make good deals with JV partners... all still without addressing anything other than zone D ???