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 ha ........

The mining method used at Panasqueira is a mechanized room and pillar method that has evolved during the past 50 years. This mining method is possible in part due to the very competent host rock, and underground rock support is rare. Blocks of ore are laid out initially in 100m by 100m sections by driving 5 m wide galleries, 2.2 m in height. The planned height of the stopes is nominally 2.2m, but increased slightly in areas where ore bearing veins are more variable in their dip, strike or thickness. A major emphasis in the stoping operation is to strive towards the 2.2m mining height in all working areas. Indicated and inferred resources are initially picked up from drillhole intersections. Potential ore/vein intersections are categories according to approximately 10m vertical slices between each main level. Stope development ramps are then driven from level to level, and approximately horizontal subdevelopment is used to access the highest ore intersection. When the ore intersections have been found by lateral development, and verified by face samples, 5m wide galleries are driven to create roughly 11m by 11m pillars. This development is laterally aligned to the mine grid system, but vertically the development is inclined up or down so as to follow changes in ore dip. Faults, divisions and other string variations in the ore intersections sometimes necessitate additional in-stope diamond drilling. Following yet more face samples, further ore extraction is achieved with mo ........

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