The history of the Ollomont-Valpelline mining complex

The first exploitation

The popular tradition attributes to a local farmer the discovery of copper ore deposits and they were first explored around 1700. In the early 18th century Count Perrone, in partnership with the lawyer Jean-François Ferrod, started the exploitation, building some factories in Valpelline and buying land and woods for timber supply. From 1700 onwards, the mine changed ownership several times: from Ferrod to the Ansermin and Gachet families, from Constantin Rosset of Ollomont to the Argentier brothers, who built a mechanized system to empty the water from the underground. The results were promising and led to a fair and reasonable profit: between the second half of the 18th century and the Napoleonic era the mine had more than two hundred employees.

The description of Nicolis de Robilant

Technical drawings of the extension work on the mining site at Les Rey.

In Ollomont it was the year 1751...

The Paduan doctor Vitaliano Donati (1717-1762) just after being appointed lecturer of Botany at the University of Turin was sent by King Carlo Emanuele III to visit the dukedoms of Savoy and Aosta learn about the mining potential of the Savoy territory and compile a map of the mines, detailing the ores and the potential for exploitation and employment of local labor of each of them. In Osservazioni di Storia Naturale ... in Savoja, ed Aosta ... anno MDCCLI about the Ollomont mine Donati wrote as follows: «It’s has been fifty and more years since this mine has been continuously exploited and therefore great excavations have been made and inside there are many caves, which might be compared to magnificent rooms ... Among the copper mines of Savoja as well as of Piedmont it would perhaps be more profitable than any other ones».

Portrait of Vitaliano Donati. Vincenzo Pinali and Giovanni Marsili Historical Library of Medicine and Botany, University of Padua.

In the first half of the 1800s

During the nineteenth century, with the expansion of the copper market it became necessary to strengthen the processes after the extraction and therefore the facilities on site were expanded and enhanced with the construction of the buildings at the mining village of Les Rey that housed different functions: the workshops for maintenance, the forge, the lodgings for miners. In 1809 the plants were equipped with a «bocard» for the crushing of the ore and with a washery. In that year the workforce was 221 and the production was 180 tons. In 1818 the mine passed to Mathieu Negri with excellent results, but after a few years the operations slowed down: the hydraulic machine for pulling the leaking water out of mine shafts broke and excavations were suspended in 1830.

General view of the buildings of the Les Rey mining complex. Plan Géométrique de la Commune d’Ollomont, Ingénieur – Géomètre Furno, 1806. – State Archives, Turin.

The Belgians are coming

In 1855 the mine was taken over by the Belgian Count Victor Seyssel d'Aix who introduced important innovations; first of all, a new dewatering machine commissioned to Innocenzo Manzetti, scientist from Aosta Valley, which allowed 200 litres of water per minute to be drained. The work resumed at full speed and the galleries were drained, the railroads were installed, the foundries were built in Valpelline and new sections of excavation were started in La Balme and Vaud. In 1864, Count Cornelissen started a new company, thanks to which the equipment was renewed, allowing the extraction of up to 12.5 tons of ore per month. Excavations continued from 1880 with the Wellens et C. Company and subsequently there were numerous company changes, also because of the diffcult working conditions due to the problem of drainage of the water in the galleries and to the diffculties of getting the forest resources used in the construction works and in the foundries.

Topographic map of the Ollomont valley. Military Geographical Institute, 1882. State Archives, Turin.

The period of greatest exploitation

Thanks to the management of the company Elzéar Alda till 1905 and subsequently of the Società Anonima Ollomont, the early years of the twentieth century were the period of greatest exploitation of the mine that employed more than a thousand workers in the area. Important expenses were a orded for the construction of American ovens in Frissonière, for the washing plant and the power plant at Ollomont. To facilitate the handling of the mineral, some new galleries were opened in the Saint-Jean section such as the Sant'Anna gallery at level of Les Rey factories. From this level three new shafts called Saint-Jean, Challant and Arolla were dug following the slope of the cultivation filons to be used for service activities such as the handling of extracted material, the access of miners and the drainage of water that flooded most of the galleries. In March 1909 the Frissonière haulage tunnel, 2.5 km in length, was also inaugurated; running from the Saint-Jean galleries it facilitated the transport of the mined material to the new foundries of Valpelline built near La Fabrique. However, due to poor performance and high costs, the operations were suspended and the equipment was sold out. An attempt to resume was made by the Società Anonima Minières et Fonderies de Valpelline but was not successful.

The construction of the new foundries at La Fabrique in Valpelline, early 20th century. Regional Historical Archives, Cogne National Society Fund.

The transition to the Società Anonima Nazione Cogne

From 1929, with the handover to the Società Anonima Nazionale Cogne the activity was resumed and the mine– then named Preslong – was exploited, especially since 1937 and for the whole war period to provide for the military needs. Some new installations were built in Valpelline aiming to modernize the production and the transport, such as the new milling, flotation and washing plant of the extracted ore delivered by a modern cableway from the Frissonière haulage tunnel. Mining ceased in 1945, when the mine was permanently closed, and the company renounced the mining concession in 1952.

The buildings of Les Rey seen from the north. Postcard, early 20th century. Photo Adolphe Freppaz, Aosta Valley Autonomous Region – BREL Archives – Domaine Fund – CC BY-NC-ND.