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Barra Verde tailings operation:
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Nomen est omen - our base, the “Tungstenio Hotel” with “Scheelita Bar” in Currais Novos.
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The Barra Verde tailings and ancient ore treatment plant, seen from Mina Brejui.
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The tungsten skarns were first mined in the 1940s, production continued until the 1980s.
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The three main mines of the region have left more than 10 Mio tonnes of tailings @ 0.15 % WO3.
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The Barra Verde tailings are being retreated by for their scheelite and molybdenite.
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Close-up view of tailings with garnet, diopside, calcite, minor scheelite, pyrrhotite, pyrite, molybdenite and chalcopyrite.
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Shaking table at Barra Verde.
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Close-up view of shaking table, the white parts contain mainly scheelite, followed by a mixture of sulfides with appreciable amounts of scheelite.
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Flotation cell at Barra Verde, the bluish black mineral is molybdenite.
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Boca de Lage tailings:
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Molybdenite concentrate
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A particularly coarse grained scheelite concentrate.
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The Boca de Lage tailings seem to contain less molybdenite, the scheelite contents are comparable to those of the other tailings.
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Typical skarn ore with garnet, pyrrhotite, chalcopyrite and minor scheelite.
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Mina Brejui:
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The Brejui Mine is the only tungsten mine in the region which is in continuous production since decades.
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One of the entrances to the mine.
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Underground workings at Brejui Mine.
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Typical tungsten skarn ore with garnet, calcite, scheelite and diopside.
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During the operation a shear zone hosted high grade copper mineralisation was encountered but was never mined.
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Close-up view of secondary copper minerals that formed in the shaft.
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Sample of high grade tungsten ore with ca. 3 % WO3, main minerals are garnet, diopside and scheelite.
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Same sample as before under short wave ultraviolet light high-lighting the scheelite.
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Due to its long operation time, the tailings of Mina Brejui are the most important of the area.
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Cafuca Scheelite Mine:
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Landscape between Cafuca Mine and Currais Novos
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Entrance to the Cafuca Scheelite Mine
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The mine was once run by Union Carbide, they produced approximately 40 t/month of WO3 concentrate.
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At least 3 high grade ore shoots are known at Cafuca. This particular one contains some 3 % WO3.
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Bodó Mine:
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Close-up view of high grade ore with garnet, diopside and scheelite.
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According to CPRM, the Brazilian Geological Survey, the main ore shoot contains some 1,300 t of WO3 (unspecified category).
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This still producing underground mine produces scheelite concentrate from a prograde skarn
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The ore mineralogy is fairly simple with scheelite, molybdenite, bornite and chalcopyrite.
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Mina di Edilson, Paraiba State:
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Their tailings as well contain appreciable amounts of scheelite in the fines.
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This highly differentiated pegmatite body contains several quartz nuclei. During the last tantalum boom, the mine produced mainly tantalite, now it produces mainly kaolinite.
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Host rocks are quartzites of the Equador Formation.
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Copper-gold- bismuth-silver pegmatite east of Parelhas, Rio Grande del Norte State:
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A lepidolite rich zone rich in tantalite (Ta >> Nb).
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Close-up view of tailings with quartz, white mica and lepidolite.
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A quite uncommon zoned pegmatite (center of picture) carrying economic grades of Cu, Bi, Au and Ag.
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Sample with secondary copper minerals (probably azurite and malachite) in coarse pegmatite.
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Tantalum pegmatites between Santa Cruz and Currais Novos:
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A particularly mica rich part of the pegmatite carrying secondary copper minerals.
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Granophyric pegmatites are only locally mineralized.
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The area around highway 427 is known for numerous columbite (Nb > Ta) bearing pegmatitic veins. The veins are 2 to 4 m wide and were mined down to depths of 15 - 20 m.
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Host rocks are metasedimentary rocks of Proterozoic age. Drainages in the vicinity carry alluvial gold of unclear primary origin.
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