Geology and Minerals
Alvão Natural Park (Portuguese: Parque Natural do Alvão) is a protected area founded in 1983, and located in the municipalities of Mondim de Basto and Vila Real, in the Tâmega and Douro Subregions of northern Portugal. Although the smallest of Portugal's natural parks, it extends through 72.2 square kilometres (27.9 mi2) of mountainous land, populated by approximately 700 locals.
Guyanaite.
Cerro Negro.
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