Technical Tips from our consultants to you.
The aim of our TECH TIP videos is to pass on the useful technical tips and advice that our consultants have gained over their years of working in the mining industry. Your mentors in a video!
TECH TIPS from Snowden Optiro
Dilution in the geological model that underpins the block model and resource estimate.
Speaker: Julian Aldridge – Principal Consultant – Geology – EMEAA
MSc Mining Geology (MCSM), MESci (Oxon), CGeol, FGS
TECH TIPS from Snowden Optiro
Rescaling when data is coming from multiple sources to the same plant in the same month
Speakers:
Ian Glacken – Executive Consultant
BSc (Hons) (Geology), MSc(Mining Geology), DIC, MSc(Geostatistics), Grad Dip Computing, FAusIMM(CP), FAIG, MIMMM, CEng
Rayleen Hargreaves – Principal Consultant & Reconcilor Product Owner
BSc (Geology, Geophysics, Geochemistry), MAusIMM
TECH TIPS
What are the Pros and Cons of Rescaling?
Speaker: Ian Glacken – Executive Consultant
BSc (Hons) (Geology), MSc(Mining Geology), DIC, MSc(Geostatistics), Grad Dip Computing, FAusIMM(CP), FAIG, MIMMM, CEng
TECH TIPS from Snowden Optiro
What is the difference between Reconciliation and Rescaling?
Speakers:
Ian Glacken – Executive Consultant
BSc (Hons) (Geology), MSc(Mining Geology), DIC, MSc(Geostatistics), Grad Dip Computing, FAusIMM(CP), FAIG, MIMMM, CEng
Rayleen Hargreaves – Principal Consultant & Reconcilor Product Owner
BSc (Geology, Geophysics, Geochemistry), MAusIMM
TECH TIPS from Snowden Optiro
Density: start measuring as soon as possible
Author: Julian Aldridge – Principal Consultant – Geology – EMEAA
MSc Mining Geology (MCSM), MESci (Oxon), CGeol, FGS
Density measurements should be taken on samples from a project as soon as possible, and ideally by multiple methods. Deposits are defined by grade & tonnage, so variations in density (spatially, across lithologies and mineralised zones) have as big an impact on total contained metal as grade. The ultimate aim should be able to model density with the same sort of spatial understanding and confidence as the grade. In most deposits there is no acceptable or suitable average global density! Mineralogical, chemical and porosity variations are the principal controls on bulk density, and these vary widely and independently across a deposit. The best way to improve confidence in contained tonnage is:
Take a large number of measurements, across the orebody, representing all lithologies and mineralisation domains. Large number means a minimum of 10% of the samples analysed for use in grade estimation.
Ideally measure by multiple methods, for comparison and verification purposes.
On multiple sample sizes; this will avoid bias, and account for the nature of the rock on different scales, incorporating changes such as mineralogy and void content.
Finally – be aware of the impact of water content, and ensure to define your density as dry or wet. Even better – quantify the water content in weight percent.
TECH TIPS from Snowden Optiro
Economics of Project Development: 4 Prime Metrics to assess a project
Author: Matt Mullins – Head of Advisory EMEAA
BSc (Hons) (Geology) FGL, FGSSA, FAusIMM, FSAIMM
TECH TIPS from Snowden Optiro
Fail-safe definition of Reconciliation
Speakers:
Ian Glacken – Executive Consultant
BSc (Hons) (Geology), MSc(Mining Geology), DIC, MSc(Geostatistics), Grad Dip Computing, FAusIMM(CP), FAIG, MIMMM, CEng
Rayleen Hargreaves – Principal Consultant & Reconcilor Product Owner
BSc (Geology, Geophysics, Geochemistry), MAusIMM
TECH TIPS from Snowden Optiro
Reconciling Ore Only
Author: Rayleen Hargreaves – Principal Consultant & Reconcilor Product Owner
BSc (Geology, Geophysics, Geochemistry), MAusIMM
TECH TIPS from Snowden Optiro
Multi-element Resource Classification
Author: Julian Aldridge – Principal Consultant – Geology – EMEAA
MSc Mining Geology (MCSM), MESci (Oxon), CGeol, FGS
Where there is significant economic contribution of elements / commodities OTHER than the primary commodity to the financial value of the deposit, the senior company geologist and CP / QP need to ensure there is sufficient confidence in all the different economic components.
Example 1: An Au deposit with economic Cu and Zn; the Au is fire-assayed and shows sufficient confidence to be modelled and classified as an Indicated Resource. The Cu and Zn has only been analysed in more recent drilling campaigns, and therefore has fewer than half the number of assayed samples in the Indicated Au zone. The spacing and sparsity of the Cu and Zn analyses mean that the same confidence in grade continuity cannot be applied as for the Au analyses.
Example 2: A hard-rock Li deposit with accessory Cs and Rb; the Li is assayed according to industry standard and shows sufficient confidence to be modelled and classified as an Indicated Resource. The Cs and Rb has been analysed in all samples using XRF, without check analyses at an umpire laboratory using an industry standard assay method.
The lower accuracy and precision (and unknown bias) of the Cs and Rb analyses mean that the same confidence in grade cannot be applied as for the Li analyses
In both of these examples, the contribution of the other commodities should not be reported as part of the overall resource statement, and should not be used as economic components during RPEEE / optimised pit shell modelling.
More Tech Tips videos coming soon!
Our consultants who have participated in these Tech Tips videos.
Ian Glacken – Executive Consultant
BSc (Hons) (Geology), MSc(Mining Geology), DIC, MSc(Geostatistics), Grad Dip Computing, FAusIMM(CP), FAIG, MIMMM, CEng
Ian is a geologist with postgraduate qualifications in geostatistics, mining geology and computing who has more than 35 years’ worldwide experience in the mining industry. Ian’s skills are in resource evaluation and due diligence reviews, public reporting, training and mentoring, quantitative risk assessment, strategic advice, geostatistics, reconciliation, project management, statutory and competent persons’ reporting and mining geology studies. Ian has a strong mining production background and is a regular auditor for the world’s largest mining companies.
Matt Mullins – Head of Advisory EMEAA
BSc (Hons) (Geology) FGL, FGSSA, FAusIMM, FSAIMM
Matt is an experienced mining industry professional specialising in creating value in resource companies through resource optimisation, project development, business improvement, and value-adding transactions. He has a strong geological and mine planning background, and a proven track record in resource and project development, business improvement, mergers and acquisitions, capital project governance, and senior management. Matt has specialised in developing and implementing global governance and best practice systems for resource companies in the areas of resource reporting, mine planning, capital governance and productivity. Matt’s range of experience includes early-stage geological and opportunity assessments; resource modelling; estimation and reporting; mine planning; strategic resource development; project evaluation and economic modelling and analysis. He has worked for large mining companies (ArcelorMittal, Billiton, BHP, Randgold Resources and Goldfields), mid-tier companies (Severin Mining), research (CSIR), as an entrepreneur (twice), and as a mining analyst on the JSE and has helped companies list on the JSE, LSE and NASDAQ. Matt is a Competent Person/Valuator in most major commodities and has worked in the key geological terrains in Canada, the USA, Cuba, Suriname, Colombia, Peru, Chile, Mali, Guinea, Liberia, the DRC, Angola, Zimbabwe, Mozambique, South Africa, India, China, Indonesia, Australia, Azerbaijan, the Ukraine, and Kazakhstan.
Snowden
Julian Aldridge – Principal Consultant (Geology)
MSc Mining Geology (MCSM), MESci (Oxon), CGeol, FGS
Julian has more than 17 years of experience as a geologist in resource assessment / mineral exploration and project management of grassroots to feasibility stage projects. He is skilled in 3D modelling, resource assessment, QAQC assessment and data/statistical analysis. He is a Chartered Geologist (CGeol) with the Geological Society of London, a Member of the IOM3 (MIMMM) and acts as a CP/QP. Before working as a consultant, Julian spent 10 years as an exploration geologist, managing drill programmes, running geochemical sampling and geophysical programmes in multiple countries. He has an excellent practical knowledge of modern mapping, sampling and analysis techniques and has spent time working on remote sites and communicating in different cultures, allowing him to develop an excellent analysis and interpretation ability. Julian has an expert knowledge of genetic and descriptive metallogenic models.
Rayleen Hargreaves – Principal Consultant and Reconcilor Product Owner
BSc (Geology, Geophysics, Geochemistry), MAusIMM
Rayleen is a mining geologist with more than 25 years’ experience in the resource industry. Rayleen has been involved with onsite implementation and administration of Reconcilor for the past 15 years and has significant expertise in mine site reconciliation. Utilising her strong domain expertise, Rayleen is the Product Owner of Reconcilor, providing a leadership role within the Research and Development team, ensuring delivery of software features and functionality that meets the needs of key stakeholders. Rayleen has authored a number of published white papers on mine reconciliation and been a speaker on the Fresh Thinking by Snowden Optiro podcasts.
Snowden Optiro – Mining Advisory Consulting, Software and Training.
Providing advice, consulting, training and innovative software solutions to mining and exploration companies, their advisors and investors.
