SAMPLING , ANALYSIS AND LAB ASSAY
Olympus has worked with both MEFFA Lab Oy on the Geochemical Research and Documentation Assistant ( GERDA , left ) and Geotek on the Boxscan system ( right ) to help automate the core logging process
The process is carried out by identifying and mapping parameters for the classification of rocks , identifying the necessary factors for classification and matching these with data from the Minalyzer CS . This process verifies which elements and / or visual characteristics were used to define the rock with data generated by the units , the company explained .
“ The output will be a trained dataset , ie an automated log ,” Minalyze said . “ The dataset will be specific to the customer , but the program will be generic , ie a framework that can be adapted for other customers and generate specific logs for their geological conditions .”
The program will then be integrated as an application in minalogger . com .
“ The project will lead to the mining industry going from traditionally logging drill cores only with visual aids to an automated process based on data ,” Minalyze said .
Automated core scanning is just one of the developments Olympus is working on .
The company , in 2021 , is continuing to emphasise the value of real-time elemental chemistry with its sixth-generation Vanta™ portable XRF ( pXRF ) analyser and near real-time mineralogy using its nextgeneration TERRA™ II portable and BTX™ III benchtop XRD analysers , it says .
Yet 2020 saw increasing XRF automation with several separate companies releasing core scanning products incorporating the Vanta pXRF , the company reports .
Long-term collaboration with Finland-based MEFFA Lab Oy saw the release of the Geochemical Research and Documentation Assistant ( GERDA ). This fully automated system is designed to test core in core boxes and soil , sediment and crushed rock in plastic bags to achieve higher sample throughput with a pXRF analyser , according to Olympus .
The system is arranged on a CNC table with a Vanta handheld XRF analyser , a high-resolution USB camera , a control module based on Raspberry Pi 3 , and software for visualising results and processing data , the company explains .
In parallel with GERDA , MEFFA is developing a
unique method known as Nugget Effect Gold Assay ( NEFFA ) to estimate gold mineralisation in orebodies exhibiting the nugget effect .
NEFFA , in this context , measures the nugget effect through multiple non-destructive , systematic pXRF analyses of a geological material ( typically crushed rock / crushed drill core ) to identify the presence of gold or other precious metals based on its average distribution within the sample .
“ Even though it ’ s in its infancy , this exciting innovation is currently being evaluated by several gold miners ,” Olympus said .
A collaboration with Geotek also started to bear fruit in late 2020 , with Geotek shipping the first of its Boxscan systems from its UK-based production line . This system incorporates the Vanta pXRF to deliver automated and simultaneous acquisition of geochemical parameters in an easy-to-use core box scanning system , Olympus explained .
Olympus has been working with Geotek for over 12 years , incorporating pXRFs on Geotek ’ s Multi Sensor Core Logging Systems for environmental and academic studies , however , the Boxscan system has been specifically designed for core trays used by the mining and mineral exploration industry .
In addition to pXRF measurements , the Boxscan can incorporate additional sensors , including infrared for mineralogy as well as magnetic susceptibility highresolution photography , colour profiling , and structural information , Olympus claims .
Todd Houlahan , Olympus ’ Director of International Mining , remarked : “ Olympus is very proud to be associated with continued innovation of pXRF technology in the minerals sector . Core scanning is gaining in popularity , and both Geotek and MEFFA Lab Oy have shown real vision in the development of their unique products to systemise pXRF data acquisition .”
To help meet the growing interest in incorporating XRF into scanning or automated systems , Olympus released the Vanta iX in-line XRF analyser this January . The Vanta iX XRF automates analysis , delivering instant results for real-time production or process line monitoring , according to the company .
“ Designed to operate 24 / 7 , the analyser can be configured to deliver pass / fail results and elemental chemistry ,” Olympus says . “ In geochemistry applications , the Vanta iX could be easily incorporated into mineral processing operations to monitor geological variability and grade .”
The Vanta iX in-line analyser incorporates the ruggedness and reliability the Vanta series is known for but allows for integration into existing robotics and other automated systems , according to the company .
Improving the quality chain
Tina Knudsen of FLSmidth believes there could be a quantum leap in mineral sampling accuracy if the equipment and processes being used in the plant were afforded the same amount of attention granted to lab instrumentation .
With FLSmidth covering the whole sampling , preparation and analysis process – from exploration and mine development , to mineral processing and product stockpiles , in both the lab and mine site – and Knudsen being Global Head of the Sampling , Preparation and Analysis Product Group , that belief is well founded .
“ In the lab , lab managers traditionally want to have the best analytical equipment , they may also want to automate some of the processes and be in control of everything that goes on within the facility ,” Knudsen told IM . “ Often it is other people in control of the equipment at the plant site , and those personnel may not consider sampling and the samplers as important as key mineral processing equipment like the SAG mill or flotation cells .”
If a miner uses an off-site laboratory , the expertise to advise on where samplers should be placed , how often sampling should be conducted and the processes needed to effectively maintain the equipment could , in some instances , be hundreds of kilometres away .
This means the on-site samplers can get overlooked , which , over time , impacts the mine from an operational and financial perspective .
There are ways to avoid this issue in greenfield operations , such as tendering for samplers at the same time as the processing / lab equipment to align
60 International Mining | FEBRUARY 2021