I noted in the 14 December MRE upgrade that the top cut for NN has been increased to 100g/m whereas it was 75g/m in the July 23 update and the January 23 update was 50g/m.
These changes by themselves should have increased the grade of NN and also increased the resources. However the grade of NN in the Dec 23 update went down slightly suggesting the new drilling results were generally lower grade than assays up to July 23.
These are the statements from the 14 December 24 July 23 MRE updates:
“Of note is the change in top cut for HG01 from 75g/t Au(2306 MRE) to 100g/t Au (2312 MRE) due to consistent zones of high-grade gold mineralisation intercepted during the 2023 drilling campaigns”
“Of note is the change in top cut support for HG01 from50g/t Au (previous MRE as at 31 December 2022) to 75g/t Au (current MRE as at 30 June 2023) due to consistent zones of high-grade gold mineralisation intercepted during the 2023 drilling campaign."
The other thing to note is that the OPVM has generally increased from the July MRE update see attached image (with my drawing of July 23 MRE update OPVM figures) which I assume is partly due to increasing the cut-off from 75 g/t to 100g/t and infill drilling. The same is noted for theJuly 23 MRE update as can be seen from the second image below - this is a significant trend whereby each MRE upgrade increases the OPVM. The increase is most notable for RL 200m, 250m, 350m, 400m and 450m where the increases are significant offset by reductions at 300m, 500m and 550m RL (all not that significant).
Hence the upgraded MRE in December 23 is due partly to infill drilling and increase in top cut grade and a significant part of the increase is due to greater OVPM in the RL that previously had an MRE. I also noted that the lower OPVM at RL 550m is probably due to the flexure zone. While the average OPVM is 1,693 from 400mRL excluding the 550mRL, it averages over 2,000.
While the grade may be lower the increased OPVM from RL400m to over 2,000 bodes well for future MRE updates.
