Recently as part of a due diligence I was reviewing a couple of 43-101 technical reports and something jumped out at me. There were pages and pages of statistical plots. The plots included QA/QC and check assay diagrams, variograms, box plots, swath plots, and contact plots. There was no lack of statistical information. However, as a mining engineer, there was something missing that was of interest to me. Good geological sections were missing.
Its seems that most technical reports focus heavily on describing the mathematical aspects of the resource, but spend less time describing the physical aspects of the geology and the mineability.
Who is the audience
It’s always open to debate who these 43-101 technical reports are intended for. Generally we can assume correctly that they are not being written mainly for geologists. However if they are intended for a wider audience of future investors, shareholders, engineers, and C-suite management, then (in my view) greater focus needs to be put on the physical orebody description.
Understanding the nature of the orebody brings greater understanding of the entire project.
Everyone likes geology
Whenever I listen to investor conference calls, many of the analyst’s questions relate to the resource and the mining operation. Essentially the participants want to know if this will be an “easy” mine or a “hard” mine.
One simple way to explain this is with good geological sections. They help everyone understand any potential issues; i.e. a picture is worth a thousand words. Good cross-sections will describe the following aspects.
The complexity (or simplicity) of the ore zones,
The width of the ore zones,
The vertical extent of geological information,
The drill spacing and drilling density,
The spatial distribution of assay information,
The grade distribution laterally and vertically,
The waste distribution throughout the mine,
The mining block size in relation of the ore zone dimensions
One can learn a lot just by looking at well presented cross-sections. The nice thing is that they are generally understood by non-technical people.
I would like to suggest that every technical report includes more focus on the operational aspects of the orebody.
My recommendation is that the following information becomes standard in all technical reports.
At least three to five cross sections through the deposit. Don’t just present a best case typical cross-section.
At least one or two longitudinal sections.
At least three level or bench plans, showing the drill hole pierce points.
Each cross section/bench plan should consist of two parts.
Part 1 shows the drill holes with color coded grade intercepts, ore zone wireframes, and lithology or rock types.
Part 2 should be a block model cross section showing the wireframes, drill holes, and color coded block model grades using the ore/waste cutoff grade as one of the clearly defined grade bins.
It doesn’t really matter if the cross- sections are included in Section 14 or Section 16 of the Technical Report. However if they are included in Section 16 then one should overlay the pit design and/or underground stope shapes onto the sections.
I also recommend NOT incorporating these cross-sections in the appendices since they are too important to be hidden away. They should be described in the main report itself.