Independent Analysis Confirms Five New Zones at Andover
Perth, Dec 22, 2023 AEST (ABN Newswire) - Raiden Resources Limited (
ASX:RDN) (YM4:FRA) is pleased to present the results of a recent mapping and pegmatite analysis program undertaken over the Andover South Lithium Project tenements.
Mr Dusko Ljubojevic, Managing Director of Raiden commented: "With ongoing work the teams are starting to define further potential on the Andover South project. On the basis of K/Rb ratio analysis and zonation mapping of all pegmatites, we have defined a further five zones of interest, which will be evaluated in more detail in the coming months. We hope that through the improved understanding of the zonation of the pegmatite field, as well as individual pegmatites, future sampling will confirm the mineral potential within the recently defined targets. The Company will re-evaluate all the target areas with the view of potentially drill testing them in conjunction with Target Area 1, the Company's established target zone.
Shareholders can be assured that whilst awaiting heritage survey dates for drill access, which are being followed up on a regular basis, the Company is diligently continuing to explore its Pilbara lithium projects, especially Andover with the aim of defining numerous walk-up drill ready targets."
Andover South Field Program
The Company engaged CSA Global to assist in a re-evaluation exercise of the Andover South pegmatite project in the Pilbara. The most recent field program included re-mapping of the defined pegmatites and analysis of the outcrop minerology with the objective of:
1) Sampling and analysis of Potassium-Feldspar ("K-Feldspar") minerals collected from pegmatites to determine fractionation states (Highly fractionated pegmatites are more likely to host lithium-caesium-tantalum (LCT) mineralisation).
2) Analysis of the fractionation trends (potassium/rubidium ratio (K/Rb)), as a guide to define additional potential zones of interest in areas with unsampled/under sampled pegmatites, and
3) Evaluate pegmatites which returned low Li2O values, to determine their degree of fractionation and potential for LCT mineralisation, not confirmed by sampling to date.
The following are the key observations on the basis of the analysis;
- Majority of observed pegmatites are classified as "complex zoned" pegmatites. In such pegmatites, mineralised zones are typically distributed around the quartz core(s) and can be variable in nature along the strike and dip of the individual pegmatite.
- In some instances previous sampling of pegmatites sampled segments of the pegmatites that have little potential to contain lithium (e.g. samples containing only quartz and feldspar, and highly weathered parts of the outer pegmatite zones). These pegmatites are still considered prospective to host lithium mineralisation and multiple zones have been identified as areas requiring resampling with new sampling protocols to be followed.
- In reference to a global dataset of K-feldspar K/Rb fractionation data (provided by CSA Global), which indicates that pegmatites globally, with a K/Rb value of <30, have the highest potential to host lithium mineralisation, it was determined that:
- The K-feldspar fractionation data from the Andover South pegmatites specifically indicate that the high-grade lithium mineralisation is associated with K/Rb values of <10. Multiple pegmatites / zones of pegmatites are fractionated (K/Rb 10-20) but are not associated with positive samples.
The most fractionated pegmatites in the Project area have K/Rb values of <10 and have coincident anomalous Cs and Ta. These very highly fractionated pegmatites correspond to rock chip samples with significantly elevated Li2O (up to 3.80% Li2O) and observed spodumene mineralisation. In this pegmatite system a K/Rb of <10 is indicative of a potentially mineralised pegmatite. Therefore, where additional pegmatites Li2O rock chip assay results were low or were not sampled for assay, they still have the potential to host lithium mineralisation.
Summary of target zones:
- Target zone 1 - has been defined across an approximate 1.5km strike extent within tenement E47/4062, with defined pegmatites which correlate to high-grade Li2O mineralisation. The K/Rb ratio data also indicates that the pegmatites in this zone are highly fractionated in this zone.
- Target zone 2 - is defined on the northern extent, and subparallel, to Target area 1. Multiple pegmatites have been mapped, but the initial sampling results did not indicate economic mineralisation. The K/Rb data analysis of these pegmatites indicates that the pegmatites are highly fractionated.
- Target zone 3 - is located on the eastern strike extent of Target zone 1, within tenement E47/4061 and is characterised by outcropping pegmatites, low lithium mineralisation rock samples, but indicated as highly fractionated by the K/Rb ratio analysis.
- Target zone 4 - is located adjacent to Target zone 3 on E47/4061 and is characterised by outcropping pegmatites, low lithium mineralisation from samples collected to date, however it is defined a potentially permissive for LCT mineralisation, as per the K/Rb ratio analysis.
- Target zone 5 - is located on the southern extent of E47/4062 and characterised as potentially permissive for LCT mineralisation, as per the K/Rb ratio analysis.
- Target zone 6 - is located on the western extent of E47/4062, and is also characterised by outcropping pegmatites, which are potentially permissive for LCT mineralisation, as per the K/Rb ratio analysis.
It should also be noted that a significant portion of the Andover South project is obscured by a thin sedimentary cover. These areas will be evaluated through a combination of soil sampling, or shallow air-core/auger drilling, with the objective of defining new potential target zones. This work will probably be undertaken in parallel with the maiden drilling program on the key target areas.
Planned work
On the basis of the analysis it was concluded to undertake further work, prior to commencement of drilling, in order to confirm further potential zones of interest, as defined through this exercise.
Planned work programs;
- Resampling of pegmatites within the new prospective zones, as defined through the K/Rb fractionation data analysis.
- Obtain high resolution drone imagery and lidar of the tenement areas to refine the digitisation of currently defined and potentially further outcropping pegmatites
- Complete a high-resolution magnetic survey over the target area, with the objective of understanding the relationship between structures, pegmatite mineralisation and potentially define a pegmatite response which may be used to determine pegmatite geometry at depth
- Refining drill planning, in conjunction with CSA Global, based on the work done to date, to ensure Phase 1 drilling will be best placed to intersect the mapped lithiumbearing pegmatites
LCT Pegmatites zone mapping
A brief examination of the host rock indicated it to be mostly weakly metamorphosed mafic units at lower greenschist to greenschist level.
Three types of pegmatitic units were observed in the area.
1. Pegmatitic core unit - strongly indurated unit of mainly quartz with varying amounts of feldspars, spodumene and micas (Figure 4a, b*). This is the least weathered of the units and sometimes shows strong silicic alteration.
2. Aplitic unit - fine grained saccharoidal unit dominated by albite and quartz, and more rarely with fine grained K-feldspar (Figure 4c, d*). The aplitic unit sometimes contains small orange to pink garnets. The aplite varies from relatively fresh to strongly weathered.
3. Pegmatitic wall unit - coarsely crystalline feldspar-dominated unit with common quartz and less common muscovite (Figure 4e, f*). Varies from megacrystic K-feldpsar and quartz to a granitic groundmass with megacrystic K-feldspar phenocrysts. Kfeldspar is the most dominant of the feldspars in this unit. In places this unit shows moderate to intense albitisation.
The pegmatitic units occur mainly as parts of more complex zoned pegmatites, containing one or more for the units (Figure 4a, e*) with a general trend from pegmatitic core to the aplitic unit and pegmatitic wall unit. The units are also observed as single veins in some places.
Examination of the previously sampled rock chips at each of the pegmatites explains the variation in Li2O content where mineralised pegmatites were sampled. The main reason is that most of the mineralised pegmatites are complex zoned, and depending on the part of the pegmatite sampled, the sample may or may not contain lithium bearing minerals.
The most abundant visual spodumene is in indurated pegmatitic core zones (e.g., Figure 5ac*), with confirmed visual spodumene up to 29% (Sample R21160) and of 2.22% Li2O.
*To view tables and figures, please visit:
https://abnnewswire.net/lnk/1K5A3M1H
About Raiden Resources Limited
Raiden Resources Limited (ASX:RDN) (DAX:YM4) is a dual listed exploration and development company which is advancing the Mt Sholl Nickel-Copper-Cobalt-Palladium deposit in the Pilbara. The Company's portfolio host metals and commodities considered critical for the energy and electrification revolution.
| ||
|
