Rock chip assays from samples have returned spodumene values ranging from 3.1% to 7.15% lithium oxide.
Geological mapping along with the sampling has confirmed some of these pegmatites as LCT (lithium, caesium, tantalum) types.
Medcalf is in the southeast part of the company’s Lake Johnson project in the southern Yilgarn region, about 45 kilometres southeast of its Mt Day prospect.
Managing director Adrian Griffin said: “The occurrence of LCT pegmatites adjacent to granites at Medcalf has regional geological significance.
“The pegmatites occur in the same greenstone sequence that abuts the same granite complex at Mt Day.
“Both locations have significant lithium mineralisation and there is good potential for locating further LCT pegmatites below cover, within the Lake Johnson project area.”
Medcalf and Mt Day add to the potential of the Lake Johnson Lithium Project within the prolific Yilgarn Block.
The Lake Johnson tenement package underlain by regional magnetic data.
This hosts major deposits at Earl Grey of Kidman Resources Ltd (ASX:KDR) and SQM, Mt Marion of Neometals Limited (ASX:NMT), Gangfeng and Mineral Resources Limited (ASX:MIN); and Mt Cattlin of Galaxy Resources Limited (ASX:GXY).
Similar geological features
These lithium deposits, as well as Medcalf and Mt Day, have similar geological features.
At Medcalf, initial geological reconnaissance was conducted after interpretation of aerial photographs highlighted the potential for multiple pegmatites in 2017.
Outcropping pegmatites were identified during subsequent field inspections in April 2018 with recent geological mapping and sampling confirming some of these as LCT types.
Pegmatite swarms containing spodumene mineralisation outcrop in a zone 100 metres by 50 metres in area, within a larger area of pegmatites 250 metres wide by 500 metres long.
Field inspection identified a pegmatite swarm centred on the highest hill in the area, where at least five pegmatites were located, and all containing spodumene.
The prospect area has moderate to low topographic relief and potential exists for additional pegmatites under cover.