Cerro Queimado, União das Freguesias de Zebreira e Segura, Idanha-a-Nova, Castelo Branco, Portugali

Regional Level Types
Cerro Queimado	Mining Area
União das Freguesias de Zebreira e Segura	Civil Parish
Idanha-a-Nova	Municipality
Castelo Branco	District
Portugal	Country

In the northern border of the Segura pluton, there is the so-called “Cerro Queimado” mining area where banded aplite–pegmatite dykes are intrusive and have filled sub-horizontally opened fractures in the metasedimentary sequence. They are sub-perpendicular to the foliation, striking N140° and dipping between 20 and 45° to the south. Other low-dipping (<30° to the south–southwest), N135°–150° aplite–pegmatite dykes are found in the southern border of the most occidental part of the Segura pluton. They occur as multi-decimetric-thick to metre-thick intrusions, which are well exposed in the river valley.
In both pegmatite and aplite bodies, albite, K-feldspars, and quartz are the main constituents, with both minerals forming bands parallel to the boundary with the host schist. Pegmatite develops as infillings of the opened fractures within the aplite dykes, usually displaying growth textures that are perpendicular to the aplite boundary. A series of phosphates, like amblygonite and other (Fe-Mn, Ca-Sr)-P phases, Nb-Ta oxides, and topaz are abundant. Both aplites and pegmatites are leucocratic magmatic facies with low amounts of black constituents, except Nb-Ta oxides and local tourmaline.

Other Regions, Features and Areas containing this locality

References