Australian exploration company Meteoric Resources (ASX:MEI) is preparing to launch a diamond drilling campaign at the Caldeira Rare Earth Element (REE) Project in Brazil.
The company says the diamond drilling program slated to begin in about 10 days will consist of 25 holes designed to test the depth of Caldeira’s REE mineralisation. Meteoric reports 20 of these holes are designed to twin historic auger holes drilled by previous explorers JOGMEC between 2016 and 2019.
All new holes will be drilled deeper than the original historic holes into unoxidised granite, which the company notes will ensure full mapping and documentation of the extensive regolith profile that hosts the REE mineralisation.
This due diligence program is part of an acquisition agreement with the Brazilian state Minas Gerais for the 21 mining licences and 9 mining licence applications that together form the Caldeira projects.
Commenting on the upcoming diamond drilling program, Meteoric Resources Director Dr Andrew Tunks says: “The first phase of our DD is now well underway with resampling of historic samples complete and samples dispatched to the laboratory. In the coming weeks we will commence a diamond drilling program which will see both twin selected historical auger holes to validate geology and REE grades, plus identify the depth to the base of the REE mineralisation.
Given the base of mineralisation is unknown, with 85% of all holes terminating in grades above 1,000ppm (parts per million) TREO (total rare earth oxides), any depth extension will impact positively on the size of any resource. In addition, some clay hosted deposits report an increase in HREE (heavy REEs) at depth. If present at the Caldeira Project this would impact positively on the REE grade of any resource.
“In addition, some clay hosted deposits report an increase in HREE (heavy REEs) at depth”
At the same time we have been busy developing links into groups with significant REE research and processing experience. The Australian Nuclear Science and Technology Organisation (ANSTO) have a long history working in the REE industry and all the initial metallurgical testwork will be completed at the ANSTO facility in Lucas Heights, Sydney.
Likewise, BNA Mining Solutions are a leading resource estimation consultancy in Brazil with significant previous involvement in the Caldeira project. Work has already commenced on the historic drillhole and assay database in preparation for modelling and resource calculations and we plan to announce a maiden resource estimate under the JORC Code early in the second quarter 2023.
Meteoric reports the new diamond drilling program will provide a geostatistic comparison of downhole grades between diamond holes and old auger. Furthermore, all new assays will be completed at the SGS-Geosol laboratory in Vespasiano, Minas Gerais.
The program will also drill beyond the current base of drilling until the granite basement is intersected to collect data on the thickness of the clay zone and the depth to which REE mineralisation is present.
In addition, the company notes the program will also provide sample material for metallurgical testwork across 6 licences, with previous testwork only being completed at the Capo do Mel Prospect.
Furthermore, the diamond drilling program will also characterise the weathering profile and rock conditions to determine the optimum drilling method for any detailed resource drill-out.
Metallurgical testwork will be carried out by ANSTO with samples collected from all drillholes to be split into 2 fractions after logging. Fraction 1 will be send to the SGS-Geosol laboratory in Vespasiano, Brazil, while fraction 2 will be shipped to the ANSTO laboratory in Sydney where they will undergo a series of mineralogical and metallurgical tests to assess mineralogical variability across the system and to optimise REE recoveries.
Meteoric also reports BNA Mining Solutions has been involved as the competent group overseeing previous exploration at the project. Historic data collected by JOGMEC includes 13,037 whole rock analyses collected from 1,311 auger holes drilled across the 6 mining licences at Caldeira. The company says work has already commenced on validating the historical database, and a maiden Mineral Resource Estimate (MRE) for Caldeira will be reported in the Q2 2023.
As part of he due diligence assessment, Meteoric resampled 31 drillholes from JOGMEC’s 2016 to 2019 drilling program, with 315 pulp samples collected from 23 drillholes, and 109 samples of original unprocessed samples collected from 8 drillholes to cover all targets previously drilled.
Meteoric’s project also portfolio consists of the Palm Springs Gold Project in Western Australia and the Warrego North IOCG Project in the Northern Territory.
Images: Meteoric Resources NL & iStock