Abandoned mines are spaces of high historic interest once they contextualize remaining aspects from the current way of living in relation to the socio-economical needs and the political strategies that vigour in the labouring period. On the other hand, the space of the mine – so many times remote – is frequently surrounded by a majestic natural/rural landscape, causing sometimes a positive scenic impact between industrial landscape and the surrounding one. This impact is given by the enormous proportion of dismounts, of the net of profound galleries that perforate the mountain, by the ruined installations, by machinery remains, ghosts of a lost micro cosmos that conditioned the life hundreds or thousands of people. This way each ruined corner, each piece of twisted and rusty iron are memory of a technique, of a time and culture that are being rapidly lost, as fast as the closures of last mines in Portugal. The culture of the mine and of mining people may still remain in the memory of the old miners, in the municipal registration books of concessions, in the magazines of the Geological Survey of Portugal, as legends or singsongs that lose with the oral tradition extinction (1).

I have already visited some of these magic places - and much more are in my agenda. Whenever I talk with an old miner or with an old person of a lost village, often in idyllic natural sceneries, my imagination becomes sepia, sometimes black and white, and memories organize themselves as if in a movie that passes in that precise moment in front of my eyes. The time stop and the emotions mixed with the vision of ruins and rusty machinery, stories of smuggling to the other side of the border turns real, we walk together the ghosts who live in the deepest galleries...



São Miguel de Acha Mines are similar to many hundreds; they were small occurrences with regional importance which by themselves would not justify more than two new lines as their full story is already written.

These were one of my first mines with the first self-collected heavy galenas. I think that this is an enough reason to remember once again these mines now almost erased from the maps.



The village of São Miguel de Acha is situated about 25 km North-Northeast of Castelo Branco. The plumbiferous deposit, made famous by Carlos Ribeiro' studies, develops, especially in the Northwest region of São Miguel de Acha. Although, mining in the region dates back to the Roman period, and continued in the medieval period and in the 19 & 20th centuries.

The lead of São Miguel de Acha promoted irregular mining activities for hundreds of years. The first geological survey "Memórias sobre as minas de chumbo de S. Miguel D'Ache e Segura" written in 1857 by Carlos Ribeiro shows that mineralization occur, in parallel lodes within the large granite patch of Castelo Branco and Idanha-a-Nova. The granite is porphyroid, consisting of white feldspar phenocrystals embedded in a coarse feldspar paste, also white, hyaline quartz, sometimes slightly grayish, biotite, and some sporadic muscovite.

Between 1888 and 1924 the metalliferous district of São Miguel de Acha gave rise to four mining concessions: “Cabeço onde Mataram os Homens”, “Barroca do Marmeleiro”, “Chão de Tirante” and “Fonte dos Sinos".


Between 1955 and 1954 were registered in the region about one hundred new mineral occurrences/deposits of lead, silver, zinc, tin and tungsten.

The mining operations were initiated by the french Brassac Georges Étienne Saint Hilaire and the spanish Boaventura Doria Borrel, from the company “Société Minière ibérique”, with headquarters in Brussels and with several interests in the region from Medelim to Vila Velha de Ródão.

The referred mining concessions, with a low ore production, have undergone a buying and selling speculative process. In 1922 these were purchased by “Minero-Metalúrcica, Ltd” which sold them in 1924 to the company “Volcano e Collares”.

In October 1942 (in the middle of the Second World War, 1939-1945), in the tungsten exploitation peak, “Sociedade Mineira de S. Miguel de Acha” was formally constituted, and finally, in 1967 the loss of concession licenses happened due to non-payment of the mining taxes.

And this was the common end to many other small mines at the time.



References:
-Ribeiro, Carlos. Memórias sobre as Minas de Chumbo de S. Miguel d'Ache e Segura, no concelho de Idanha-a-Nova e Castello da Ribeira das Caldeiras, no concelho do Sardoal. Lisboa Typ. da Academia das Ciências, 1859, 52p.
- Thadeu, D., 1951. Geologia e jazigos de chumbo e zinco da Beira Baixa. Bol. da Soc. Geol. de Portugal, 9 (1-2), 144p.
- C. M. de Idanha-a-Nova webpage.
- (1) Geomining Heitage in the Naturtejo Area; Carvalho, C.N., Gouveia J., Chambino, E., Moreira S. - Actas III Simpósio sobre Mineração e Mineralogia Históricas no Sudoeste Europeu, Porto, 2005.