Management Team

Lithium-caesium-rubidium

A new style of large-scale deposit

During a 2016 drilling program targeted at tantalum-lithium bearing pegmatites at Buchanan Creek, SMA identified “metasomatic lithium mica” mineralisation within the surrounding country rocks (mica schists) as a result of an influx of lithium bearing solutions. Drill holes SMA 002 & SMA 018 intersected grades of lithium mineralisation similar to those of large scale micaceous lithium deposits of the San Jose type.

Petrography of drill core confirmed a secondary lithium-bearing mica was present in the country rock mica schists. This style of mineralisation is similar to the large tonnage medium grade San Jose Lithium-Tin Deposit located in Spain, 75% owned by Infinity Lithium Corporation (ASX Code INF). Here lithium and associated elements were deposited directly into the host sediments overlying the source lithium-bearing granite. Similar deposits of this large to very large tonnage, low-medium grade type include Sadisdorf and Zinnwald in Germany and Cinovec in the Czech Republic.

SMA conducted a sampling program of the termite hills in the Buchanan’s Creek area to determine the sub-soil geochemical signature. The figure below shows a significant lithium surface anomaly exists over the hinge fold area at Buchanan’s Creek, a locality near Georgetown, North Queensland. The lithium anomaly correlates well with current data such as pegmatite distribution, drill core assays, stream drainage sampling and field observations.

In February 2020 SMA was awarded a Collaborative Exploration Initiative grant by the Queensland Government to study the mineralisation and evaluate the economic potential of this “new style of deposit”.

As a result, SMA identified that a significant metasomatic event occurred in an area associated with the emplacement of the Buchanan’s Creek lithium-bearing leucogranite. During this event the alkali metals; lithium, caesium, rubidium and potassium streamed from the intruding granite at high temperature and altered the country host rocks to form lithium mica schists. This work indicates the potential for economic deposits of lithium-caesium-rubidium mineralisation and that targeted exploration is warranted.

The advantage of the “new style” lithium mica deposits lies in the low cost of beneficiation and metal extraction compared to traditional spodumene deposits and the presence of caesium, rubidium and potassium as recoverable by-products.