Almonty Industries Inc. owns 100% of BVI (Beralt Ventures Inc.), a body corporate pursuant to the laws of British Columbia, Canada. BVI owns 100% of Beralt Tin & Wolfram (Portugal), S.A, which in turn is the 100% owner of Panasqueira Mine.
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Summary:
Panasqueira is a vein type deposit located in the Center Iberian Zone of Portugal, where several tungsten mines have been worked during the 20th century. These are generally accompanied by granite outcrops intruding schist and slates. There are different kind of tungsten-host structures, but the more frequent are sub-vertical quartz veins close the contacts with granites, or even inside them. At the current time, the Panasqueira mine is the only active tungsten mine in Portugal.
The Panasqueira deposit consists of a series of stacked, sub-horizontal, hydrothermal quartz veins intruding into the Beira schists containing wolframite mineralisation, which occurs as very large nugget-like crystals of large crystal aggregates, usually concentrated towards the margins of the quartz veins or, occasionally, closer to the central portion of the veins. The overall mineralized zone has dimensions of approximately 2,500m in length; 400m to 2,200m in width and at least 500 m in depth.
Historically, mining has progressed from the upper levels to lower levels, which are spaced 60 – 90m apart. Typically seven or eight flat dipping veins occur from one level to the next, with an average thickness of 0.3 m (range 0.1-1.0m). These host the economic mineralization over continuous strike lengths of 40 - 100 m. These mineralized quartz veins located throughout all mine levels, typically pinch out and later re-occur. Resources occur over five levels – Level 0 to Level 4.
Even though the mine has been in operation for more than 100 years, very little primary exploration has been done outside the active or past mine workings. The hills surrounding the mine contain many old pits and shafts left from old small tungsten vein hand mining operations. A regional stream sediment geochemical survey carried out between 1982-1984, some exploration drillholes and a lithogeochemical survey over selected areas in and adjacent to the Panasqueira returned areas of tin and tungsten anomalies.
Exploration drilling for additional resources and reserves, in advance of production, continues as the normal course of mine activities. To date, more than 80 diamond drillholes have been completed from surface, but these holes commonly flatten considerably as they deepen and are therefore limited for assistance with vein location. Underground drilling has now covered over 4,000 drillholes, mostly of 46mm diameter. A combination of a historic fire and core dumping has left the operation with a relatively small collection of core available for review. The company, through its past experience, considers quartz veins exceeding 18cm in width to be significant and so future underground development is generally based on those intercepts.