JORC 2012 Mineral Resource
Lunnon Metals has applied significant attention to the review and analysis of the former WMC reported mineral inventories to upgrade and report these in accordance with JORC 2012 guidelines. The work carried out by the Company included a detailed audit of the historical data and historical drill core that supports the current Mineral Resources, including:
• duplicate sampling with QAQC (insertion of certified reference material or sample standards)
• density determinations
• check geological logging
• mineralisation characterisation for metallurgical considerations
• historical section and plan reviews (in 2D and also in 3D as scanned and geo-referenced images)
• review of paper geology logs, assays and surveys cross referencing with the digital database
The current (April 2022) JORC 2012 Mineral Resource for the Kambalda Nickel Project is as follows (all reported above a 1.0% Ni lower cut off).
All material modifying factors have been considered and accommodated in the chosen reporting cut-off grade, which is >1.0% Ni. Refer to the ITAR in Schedule 3 of the Prospectus (dated 22 April 2021) released to the ASX for further details, the Competent Person and Important Statements for the Mineral Resources estimates for the nickel deposits on this website which also contain additional information required by ASX Listing Rules 5.8.1 and 5.8.2 and the ASX announcement dated 22 April 2022 in relation to the N75C figures.
In January 2021, Cube Consulting Pty Ltd (Cube) estimated a Mineral Resource for the 85H nickel surface in the main Foster area. Drillhole data and geological interpretations were supplied by Lunnon Metals and Cube produced the estimate using standard processes and procedures including data selection, compositing, variography, estimation by ordinary kriging (OK) and model validation. Estimates were made for nickel and bulk density only.
In December 2020, Cube estimated a Mineral Resource for the Foster South nickel deposit. As with 85H, drillhole data and geological interpretations were supplied by Lunnon Metals and Cube produced the estimate using standard processes and procedures including data selection, compositing, variography, estimation by OK and model validation. Estimates were made for nickel and bulk density as well as the minor elements of arsenic, cobalt, copper, iron, magnesium oxide (MgO) and sulphur. Furthermore, estimates were made for all variables in the background ‘halo’ domain (outside the mineralised lodes) for potential future mine planning purposes (e.g. dilution calculations).
In November 2020, Cube estimated a Mineral Resource for the Warren nickel deposit (formerly known as Foster NW). As with 85H and Foster South, drillhole data and geological interpretations were supplied by Lunnon Metals and Cube produced the estimate using standard processes and procedures, including data selection, compositing, variography, estimation by OK and model validation. Estimates were made for nickel and bulk density only. The focus of the estimate was the high-grade mineralised lodes, but estimates were also made for the adjacent hangingwall and footwall lower grade oxide mineralised lodes. Unlike the 85H and Foster South areas, the Warren Shoot comprises a large number of separate mineralised zones, both on the komatiite-basalt contact and higher up within the ultramafic sequence, as hangingwall mineralisation. Compared to the Foster South mineralisation, the Warren Shoot area has been relatively well-drilled from the surface and from the access decline. The basalt ‘trough’ is narrow but is well-defined and constrained by drilling.
In March/April 2022, Cube estimated a Mineral Resource for the N75C nickel deposit. The N75C Mineral Resource comprises the laterally continuous N75C, 18C and 24C nickel surfaces. The N75C is a flanking basal contact surface located up-dip from the main incised Foster nickel channel. The N75C mineralisation itself is of moderate nickel grade largely characterised as 5-40% disseminated nickel sulphides increasing in intensity towards the base where there can be a narrower zone of stringer to massive nickel sulphides.
To the south the N75C surface continues and becomes the 18C and sitting down flank of the N75C and 18C (and immediately above the main Foster channel) is the 24C which has a footwall almost exclusively of Lunnon Basalt. Estimates were made for nickel and bulk density. There has been previous mining at N75C, so mining depletion was required and applied.
The N75C surface was one of the many nickel surfaces mined during the operational life of the Foster mine. Total mine production recorded over 61,000 tonnes of nickel metal produced from some 2.37 million tonnes of ore. The location of these newly estimated nickel surfaces relative to the Foster workings are shown below.