Uis

Overview

The Uis Lithium Tin Tailings Project is located in central Namibia near the town of Uis, 220 km north of Walvis Bay, Namibia’s largest commercial deep-water port. The project is connected by dirt and asphalt road to the port.

Montero has the opportunity, under the terms of a Heads of Agreement (MOU) and subject to regulatory approval, to acquire a 95% equity interest in the Uis Tailings Lithium Project. Under the terms of the MOU Montero would acquire its interest by committing to milestone payments totaling US$1.42 million to the owners and by paying C$125,000 cash or shares to Lithium Africa 1. Due diligence has been successfully completed and resource and metallurgical testwork is proceeding.

History

The Uis mine operated from 1924 to 1990 with confirmed ore tonnage production mined between 1966 and 1981 of 10,657,075 million tonnes (ISCOR 1982, US Bureau of Mines, 1992). Previous and mining post ISCOR records provide a total potential tonnage of tailings of up to 20 million tonnes derived from approximate surface measurements and density estimates from a drill program conducted in 2016. A review of available surface and drill data is underway with check assays, density measurements and topographic surveys. Further work including tonnage and resource estimation, mineralogical investigations, and preliminary metallurgical testwork is in progress and updates will be provided.

The Uis tin mine ceased operations in the 1980’s and never exploited lithium. Recent drilling of the tailings confirmed the presence of lithium and tin with average values of 0.42% lithium (Li2O) and 523 ppm tin (SnO2) from the drill data.  There is an estimated potential of up to 20 million tonnes of tailings in the form of sand and slimes tailings. Renewed interest in lithium to meet future battery demand for the burgeoning electric car battery market has focused Montero to re-examine the potential of tin districts in LCT pegmatites to host significant tonnages of lithium to meet the expected demand.

Geology

The Lithium-Cesium-Tantalum (LCT) pegmatite field that host the Uis Tin mine are hosted in metasedimentary units of the Damara Mobile Belt, the northeast-trending branch of the Neo-Proterozoic, Pan African Damara Orogen in the Erongo Region of Namibia. The unzoned albite rich pegmatites at the Uis Tin mine belong to a group of highly fractionated, cassiterite and lithium-rich rare metal pegmatites.

Mineralogy

Preliminary analysis of the 2016 drill hole assay data shows that the samples range in lithium content from 0.07% to 0.73% Li2O, the tin content from 12 ppm to 1,752 ppm SnO2, and tantalum content from 1.5 ppm to 114 ppm Ta2O5.

Recent drilling of the tailings confirmed the presence of lithium and tin with average values of 0.42% lithium (Li2O) and 523 ppm tin (SnO2).