Start with some background on the OS issue and how TB has been...

Start with some background on the OS issue and how TB has been developed so far. The interp pre-mining was a near-surface layer of induration overlapped the west dipping ore lode near surface but not at depth. The OS recorded at depth below the strongly indurated zone was interpretated to be more typical patchy and/or micro-scale cemented grain aggregates unlike the continuous upper indurated overprint. An east-west cross-section shows this where interp, crossing the test-pits, starter pit, HG portion of the first 8 year pit shell and starter pit.

Sat images showed the progression from starter pit east, then moving north in April. The sonic drilling has only just started at best judging by the line clearing that only began ~1st May and what this image from the 9th shows was only half cleared by the 7th. That is some serious infill drill programme at 50m line spacing, and I assume 50m centres along each line. That sort of definition is smart geology because you can strip out holes and determine at what drill spacing OS definition becomes unsatisfactory, and thus prove what sonic hole spacing is required to test the entire deposit moving forward. Still, lot of drilling and nobody goes into that expense and detail unless the danger is serious...



Taking away the sat map, we can see the cross-section running through the starter pit high grade area in hot pink (actually the test and starter pit begins at the west end of the X-section) and the first pit move east to the end of the X-section. The X-section shows the geology interp... pink ore lode dipping west with a variable "Indurated Sandstone" cutting into the upper ore seam in the east.



The big issue spooking the market is that the lower part of the ore seam in pink, especially to the west where it dips under the indurated sandstone, is supposed to be non-indurated and not a big problem. Having mined to the base of the ore seam for a number of months now, obviously the majority of the ore mined comes from the lower part of the ore seam below the interpreted upper induration zone. The large amount of ore lost to OS (only 75% of expected u/size ore sand sent to the WCP vs expected) is being lost from the entire ore seam obviously, although the OS problem presumably was worse in the east.

The black dashed line shows the 'strike' of the lithology dipping west, at the westerly limit of mining to date. Line clearing for the sonic rig shows the plan is to test the ore seam as it dips deeper immediately west of the starter pit area up against the black dashed line. That will be the next pit to mine imo once the test drilling is completed. That way they can both test if the OS issue keeps extending to depth away from the surface indurated sandstone, and also test how well the sonic drilling predicts the OS distribution.

One of my issues atm is the zircon product produced last Qtr isn;t matching any sensible variable assumptions... there is simply more product than 1,056,500t @ 13.6% HM can realistically deliver. The answer may help solve the low zircon concentrate price, which also doesn;t match up to Bridge St explanation or my maths? Still, what's life without riddles to solve...