Category Tech talk

Authors: Ian Glacken – Director of Geology and Paul Blackney – Principal Consultant What to do if you have conditional bias:  Get more and closer-spaced data, estimate into larger volumes (this generally works – but not always), think about a…

Author: Ian Glacken – Director of Geology Stockpile volumes:  Remember that if you have a large stockpile, and particularly one which has a second layer on it, that you will need to increase the loose rock bulk density as compression…

This week's 30 Seconds of Info is from Ian Glacken our Director of Geology. Who does the reconciliation? It shouldn’t matter! A robust and auditable reconciliation system is one within which the outcome doesn’t depend upon the operator. In other words, the flow and the data reduction and processing should be totally objective – any approach which relies on individual subjectivity is doomed to failure.

Where is the mine/mill changeover point?  Surprisingly, it’s not always at the same place at every mining operation.  The logical point for the end of the mine recording (claimed tonnage and grade) is when ore goes into the primary crusher,…

What is the sampling contribution to the nugget effect? Remember that the sampling error can influence the nugget effect of an orebody, but that the nugget effect, as inferred from a variogram can have more than one component; the inherent…

Ian Glacken, Director of Geology, has written an article titled Geology, grade and geometallurgical modelling - spoilt for choice? The article discusses the extensive breadth of tools available to aid geological, grade and geometallurgical modelling - covering the evolution of modelling practices, the software choices and how in the pursuit of best practice we usually need to use up to 4 or more separate software products, and the critical need to record the increasingly complex workflow communication.

This week's 30 Seconds of Info comes from Ian Glacken - Director of Geology. Don’t forget density QAQC: In some orebodies the bulk density or specific gravity is not a major contributor to the outcome, but in the majority of deposits it is as important to get density right as it is to ensure correct assays. This means having a density standard (an aluminium cylinder is preferred) and thinking about doing density duplicate measurements. The concept of a blank is not so applicable. Of course correct bulk density determination is critical for an orebody with oxide and transitional weathered material. iglacken@snowdenoptiro.com

This week we have 2 x 30 Seconds of Info and they are about Reconciliation. They are from Ian Glacken - Director of Geology. The topic titles are: Stockpile sampling methods that don’t work; and Beware temporary stockpiles underground.

This week's 30 Seconds of Info is from Ian Glacken - Director of Geology. Sampling Theory and Practice: Be sure to check the orientation of the cone splitter daily. While a cone splitter should and generally will give a matched (equiprobable) pair of field duplicates, the orientation of the splitter is all-important in determining this. The long axis of the splitter needs to be vertical and the widest part of the splitter, i.e. the join between the cone and the chute, needs to be horizontal. This should be checked daily with a magnetic clinometer. iglacken@snowdenoptiro.com