The Richmond Vanadium project lies on the Flinders Highway and Great Northern railway, 500km west of the Townsville port and 250km east of Mt Isa. The project comprises four main prospects in the Richmond and Julia Creek districts covering an area of 1,520km2.
In March 2017, the Company entered a strategic development Joint Venture (“JV”) with Richmond Vanadium Technology Pty Ltd (“RVT”). The JV covered Horizon’s 100% interest in the Richmond vanadium project comprising 1,550km2 of Cretaceous Toolebuc Formation.
The JV (75% HRZ and 25% RVT) owns 100% of five Mineral Exploration Permits (EPM25163, EPM25164, EPM25258, EPM26425 and EPM26426) covering 481 Blocks near Richmond and 100% of the metal rights to Global Oil Shale Plc’s Julia Creek (Burwood) MDL522.
RVT completed the initial earn in period (A$1 million to earn 25% interest) in March 2018 and have commenced the second stage expenditure commitment of A$5 million over 3 years inclusive of a Feasibility Study to earn a further 50% interest in the project.
Under the terms of the JV, RVT have been sole funding and managing the earn in period under direction from the JV committee which has representatives from both parties. Upon RVT satisfying the earn-in terms, each party will contribute to ongoing expenditure in accordance with its respective percentages.
The JV conducted additional drilling in 2019 and updated the Mineral Resource Estimate in 2020 in line with the JORC 2012 Code to:
1,838 Mt at 0.36% V2O5 and 256 g/t MoO3 at a 0.30% V2O5 lower cut-off grade.
The scale of the project places it as one of the largest undeveloped vanadium resources in the world, which is close to surface and remains open in all directions. The Richmond-Julia Creek project is located within marine sediments of the Early Cretaceous Toolebuc Formation which is a stratigraphic unit that occurs throughout the Eromanga Basin central-northern Queensland. The Toolebuc sediments consist predominantly of black carbonaceous and bituminous shale and minor siltstone, with limestone lenses and coquinites (mixed limestone and clays). It is composed of two distinct units representing two different facies; an upper coarse limestone-rich-clay-oil shale unit (coquina) and a lower fine grained carbonate-clay-oil shale unit. As noted above, the Richmond Mineral Resource is hosted in soft oxidised marine sediments as opposed to the majority of global vanadium resources found in hard rock resources, lending itself to lower cost mining and processing compared to the hard rock resources.
Since commencement of the JV, RVT have conducted extensive metallurgical test work initially focussed on upgrading the run of mine ore prior to downstream processing of the concentrate. Results from the concentration tests using simple screening, gravity and flotation mineral dressing techniques produced excellent results with the concentrate comprising 21% of the original mass at an improved grade of 1.6% V2O5 and a 73% recovery. The concentrate produced also had a greatly reduced calcium content enabling a number of downstream processing options to be pursued.
Recovery Rate (%)
Downstream pilot plant testing utilising conventional proven roasting and acid leaching techniques produced commercial grade vanadium pentoxide with acceptable recoveries.
With the success of the pre-concentration and downstream test work, work has now advanced to simulated production tests. These tests are to be conducted with semi-industrial scale samples through the entire process flowsheet from samples to final product. An additional 3-4t of new samples have been dispatched to the metallurgical laboratory to ensure the most representative samples. Results from these advanced tests are expected in the September Quarter 2020.
The Lilyvale Deposit is located 45km northwest of the Richmond Township and in close proximity to the Flinders Highway and Great Northern Railway line. The deposit is 5-10m thick, up to 4km wide, over 5km long and is open along strike.
The mineralisation commences 2m from the surface and, as with all the prospects, occurs in two different facies:
- Oxidised coarse limestone rich clay unit from surface to 15m depth where the oil has been leached out and enrichment of vanadium and other metals has occurred. Previous test work has shown that over 90% of the contained metal lies in the -38µm size fraction
- Fresh fine grained carbonate – clay – oil shale unit containing vanadium, molybdenum, nickel, copper and significant oil content of 65-75 litres of oil per tonne of shale.
In 2019, RVT completed an infill drilling program on the Lilyvale deposit comprising 333 aircore holes for 7,817m with the aim of the drilling to infill and enable an updated Mineral Resource estimate at an improved JORC Category from Inferred to Indicated. In addition, the drilling provided a large metallurgical sample representative of the orebody for concentration and downstream processing testwork.
The Mineral Resource Estimate in accordance with JORC (2012) totals:
560 Mt grading 0.48% V205 for 2.6Mt V205 and 213 g/t Mo and 277g/t Ni at a 0.30% V205 lower grade cut-off.
Mine optimisation studies and commercial evaluation will now be completed on the updated Lilyvale resource model and, in conjunction with further metallurgical testwork, form the basis of the Feasibility Study.
Given the scale of the Lilyvale project and the potential to produce globally significant quantities of both 98% flake and electrolyte from this resource alone, the key focus of the Study will be to determine the optimal concentration and downstream processing flowsheets and associated capital and operating costs. Further discussions will then be held with potential offtake partners within the steel and energy storage market providers.