Gold Mountain says a stream sediment sampling program has picked up anomalous lithium and noted pegmatite signatures in four of its five Juremal licences in Brazil and has defined targets for follow-up soil sampling to home in on the sources of the lithium anomalies.
The most anomalous ground is shown to lie along north-south regional trends that have been mapped as containing granitic pegmatites either in thin cover overlying the western margins of regional-scale, late-Archean granites to the east, or between 2km and 5km of and parallel with the granite contact.
The three best stream anomalies appear to be associated with west-flowing tributaries, originating at or beyond the eastern boundaries of the easternmost block of licences, feeding into a prominent north-south drainage passing through the long axis of the same licences. They are distinctly in the tributaries and not in the main drainage.
A small, but significant lithium anomaly has also been identified in the smallest licence about 5km west of the main group, in a west-flowing tributary flowing into a different north-south drainage. No significant lithium anomalism has been reported from thin sampling of the south-western licence area.
The Juremal ground contains mapped pegmatites that extend regionally well beyond the tenement area. Management says pegmatites have been known previously to exist in three of the Juremal tenements, but due to severe lateritic weathering, only low lithium values have been identified to date.
Additionally, the Brazilian Geological Survey has observed and field-mapped potential source granites for the pegmatites in the locality.
In general, the Juremal anomaly location, with respect to locally and regionally-mapped lithium pegmatites and the proximity to the granite contact, is consistent with that of the Jaguar lithium project, about 50km to the south. The terrain between the two areas is now recognised as being part of an emerging prospective pegmatite and lithium belt.
The Jaguar ground was explored briefly in June, with first pass drilling by Solis Minerals. Solis reported lithium mineralisation occurring as “massive spodumene crystals” and rock-chip sampling yielding grades of up to 4.95 per cent lithium oxide.
Solis at the time dubbed Jaguar as “exciting” as it is the first asset in Brazil’s Bahia province to have been identified with a lithium-caesium-tantalum (LCT)-bearing pegmatite sticking out of the ground. It believes the pegmatite has a central core zone of about 50m wide.
But Solis says it was unable to renegotiate an extension of the due diligence period and did not proceed with the Jaguar project, dropping the option agreement it had signed at the end of May.
Interestingly, the Juremal project is also about 33km north-east of Gold Mountain’s Salitre project.
In October, the company reported it had picked up lithium in soil samples from a 2.5km-long zone based on contouring using a lower cut-off grade of 60ppm lithium from 855 geochemical samples on a 400m-by-50m grid in the central and northern parts of its Salitre ground.
It said the north/north-east-trending Salitre anomaly could extend to 8km in length, showed anomalous values of caesium, tantalum and tin and remains open to the north and south, with two other nearby anomalies also needing more sampling to resolve.
Management notes that the geochemistry at Juremal shows that lithium only has a weak correlation with tin, but not with other LCT elements. Tin also only shows weak correlation with LCT elements.
However, Gold Mountain adds that overall correlations demonstrate an LCT association, modified by severe leaching and possibly regional variations in lithium-associated minerals. It ultimately takes the view that lithium is its own best indicator, possibly due to the pervasive laterite weathering for which the area is noted.
The company is planning to pick up its activities in April, after the wet season, with detailed mapping and soil sampling that will likely take about four weeks. The results will be expected back after a further six weeks and in the meantime, management will undertake the necessary internal and regulatory requirements for follow-up drilling.
Gold Mountain is onto a favourable lithium trend in a good geological address that warrants follow-up. While the sources of the stream geochemical anomalies cannot yet be precisely determined, that will be the object of the imminent soil sampling program … and then the company may know if it has another Jaguar by the tail.
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By Doug Bright
