Aldoro to drill high-grade rubidium-lithium pegmatites

Aldoro Resources is just days from starting to drill at its high-grade rubidium-lithium pegmatites at the company’s Wyemandoo project, 60km southeast of Mt Magnet in WA.

The initial program plan is for 3500m of drilling spread over 48 RC angle holes ranging from 80m to 150m in depth. Previous surface sampling returned high-grade rubidium to 1.82 per cent and lithium up to 1.08 per cent.

Mapping and rock chip sampling completed in 2021 showed an extensive network of rubidium-lithium pegmatites, including loop structures, partially obscured by surficial cover soils. Drilling aims to confirm the orientation, thickness, depth and mineralisation grade within pegmatites.

The pegmatites at Wyemandoo are classified as lithium-caesium-tantalum or LCT pegmatites that also host the world class Wodgina and Pilgangoora Pilbara lithium deposits. Aldoro says other strategic rare earth elements occur in the pegmatites including rubidium and niobium. The company has identified over 1000 features from satellite imagery that may represent pegmatite dykes and plugs.

In April 2002 Aldoro completed a $2.3 million placement to fully fund the Wyemandoo drilling program.

Rubidium is often considered a pathfinder element for lithium, however the high rubidium grades at Wyemandoo has Aldoro considering the possibility of a rubidium-led project with lithium credits.

Typically found in pegmatite rock rubidium is associated with the mica mineral lepidolite that is also a lithium ore mineral. Interestingly conversion of lepidolite to lithium hydroxide takes place at approximately one quarter of the cost per tonne when compared to lithium hydroxide production from spodumene.

The mineral associations may become an important cost advantage if lithium is present in lepidolite as currently indicated.

Recognising the need for early metallurgical testing to see how to release the value rubidium brings to the project, Aldoro has appointed Dr Zhiguo He of the Central South University of China to undertake a commercialisation review of the rubidium-lithium mineralisation contained within the companies Wyemandoo and Niobe projects.

Professor He’s eight-month review will include processing and beneficiation studies to determine the most economically-viable beneficiation process at current product prices. The study will also determine which beneficiation process produces the highest rubidium-lithium concentrate grade at the most efficient recovery of contained rubidium-lithium.

Professor He has a strong research focus on the beneficiation and extraction of rare metals such as rubidium and lithium from a variety of minerals. Most importantly he has recently completed separability and extractability projects for five large rubidium-lithium mines in China.

Rubidium is not stable at room temperature when exposed to water or oxygen, so it is generally sold as rubidium carbonate. Recent 99 per cent pure rubidium carbonate prices are US$1075/kg but can increase five-fold for higher purity products. Under this pricing model the mineral works out to an eyewatering figure of over $1 million per tonne.

Rubidium industrial uses include fibre-optic cables, GPS systems, sodium ion batteries and solar panels.

Aldoro has a large number of high-grade rubidium-lithium rock chip assays and pXRF readings that correlate well with the laboratory assays. Mapping has shown an extensive pegmatite dyke swarm making the drilling the last piece in the puzzle.

Early metallurgical studies are underway to ensure delays are kept to a minimum in what could be a game changing exploration and development scenario.

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