In 1720 following the provisions of the Treaty of the Hague the island came under the rule of the House of Savoy, who acquired the title of Kings of Sardinia. The State of the Savoy boosted again the mining industry. Even under the Piedmontese mining was connected to the assignment of general concessions for the execution of research and mining operations on the whole territory of the island. The first who obtained this kind of concession, that lasted twenty years, were Pietro Nieddu and Stefano Durante.
In 1740 the general concession, lasting thirty years, was assigned to the British Charles Brander, to the baron Karl von Holtzendorf and to the Swedish consule in Cagliari Karl Gustav Mandel. According to the agreement, the concessionaries should pay to the King's Treasury 12% of the extracted galena and 2% of the silver for the first 4 years, 5% for the following 6 years and 10% for the remaining 20 years. The obligatory taxes had to be paid at the dispatch for exported commodities and within six months for those that had been sold into the island. The new company, boosted especially by Mandel, introduced some technological innovations, among which the use of the explosive during mining operations. Handwoks skilled in mining industry were brought to Sardinia especially from Germany. Mandel also built by Villacidro a large lead foundry. He was though accused by the Real Intendance of neglecting the exploration of new mines confining himself to exploit the existing ones. An enquiry was also opened for alleged fiscal illegalities that led in 1758 to the repeal of the concession of Mandel.
In 1762 the direction of Sardinian mines came into the hands of the Director of the mining district Pietro De Belly, who hampered private mining industry maintaining it was more profitable for the State to exploit directly the richness of Sardinian underground. Belly tried also to reintroduce forced work in mines and for this reason he merited in 1771 a criticism from Quintino Sella.
Among the shortcomings that should be ascribed to Belly there is also the lack of exploitation of the rich silver vein in Sarrabus, the potentiality of which Mandel had already guessed. Belly maintained it was too costly to mine in this field because of the inaccessible ground and the difficulties in communications in the area. Only within the following century the mineral value of south-eastern region was discovered again.
The last years of the 18th century were anyway important years for Sardinian mining industry; traces of iron were discovered near Arzana and of antimony in the vicinity of Ballao. At the beginning of the 19th century in Sardinia there were 59 mines, mainly of lead, iron, copper and silver. With the renewal of the fervour of mining, some Piedmontese adventurers and from some other European countries had their go too. Among them there was also the French novelist Honoré de Balzac who in 1838 started off a disastrous enterprise that had the purpose of exploiting ancient lead-bearing wastes of the Nurra.
In 1840 the new mining act was passed, which prescribed the separation of property of ground from that of the underground. According to the new act everyone intending to carry out mining prospecting would require authorization: a permit written by the owner of the ground on which the research was to be performed was required, but, if the owner of the ground opposed the request and the refusal was not considered adequately evidenced, the Police chief could act officially to allow the permit. The only obligation due to the concessionary was to pay to the Treasury three per cent of the value of mined minerals and to pay the damages to the landowners for caused damage. This law was fully enacted in Sardinia only in 1848, after the "perfect fusion" between Sardinia and the countries on the continent under the rule of the House of Savoy had completed. The new act eased the achievement of mining concessions, calling back onto the island many managers, particularly from Liguria, Piedmont, and the first Societies, with the purpose of exploiting the promising Sardinian ore bodies.
In 1848 the Sardinian entrepreneur Giovanni Antonio Sanna became the owner of the Montevecchio Mine, localised in the South West of Sardinia, it was the main mining site in Italy. He started modern industrial mining activity in the area.
Among these there was also the "Società Nazionale per la coltivazione di miniere in Sardegna" of Genua that tried in vain to achieve general concession. This kind of concession was in fact formally forbidden by the new act, in order to prevent the establishment of monopolies in mining industry. The project of the National Society came to nothing. The opening of a great number of companies was marked by the same protagonists of the project of the National Society, in order to hold anyway the majority of the highest possible number of permits. The majority of mining societies operating in Sardinia depended then on a non-Sardinian capital money. A remarkable exception was the Sardinian manager Giovanni Antonio Sanna, who achieved in 1848 a perpetual concession on about 1200 hectares located in the area of Montavecchio. Not all societies that were founded in this period had the techniques to launch themselves on the market, many of these went bankruptcy and some other got fused giving birth to greater and more reliable Societies.
In 1858 the exile Enrico Serpieri from the Romagna founded the foundry of Domusnovas for the exploitation of lead mineral in previously processed waste and not so much later of a second one in Fluminimaggiore. In 1862 the two foundries of Serpieri produced 56% of the whole Sardinian lead that had been excavated by previous waste.
Since 1850 limited groups of specialised workers from Styria, Austria, followed by German miners from Freiburg began to settle temporarily in the Iglesiente in particular in the mining areas of Monte Vecchio, Guspini and Ingurtosu . Some German influenced building and toponym is still visible in this area. The contemporaneous migration flow from the Italian peninsula towards the Sardinian mining areas of Iglesiente was more considerable and more stable ; these miners came mostly from Lombardy, Piedmont, Tuscany and Romagna. According to an 1882 census realised by the French engineer Leon Goüine, in the south-western Sardinian mines worked 9.780 miners, 3.571 of which were of mainland Italian origin; most of them settled in Iglesias and frazioni .
From 1865 onward lead and silver, by then the most extracted minerals on the island, were added to a third one, zinc, and in fact that year in the mine of Malfidano in Bugerru, the famous "calamine" (zinc silicates) were found. About 1868 dynamite was introduced in Italy, invented the year before by the Swedish chemist Alfred Nobel. Within a short time this invention revolutionised the mining techniques allowing the operation at relatively low costs even in humid yards. Meanwhile, the uneasiness of Sardinia within the recently constituted Italian State was growing up. In 1867 Sardinian members of parliament asked Prime Minister Bettino Ricasoli for a greater commitment of the State to alleviate poverty conditions of the people on the island. In April 1868 the social malaise caused in Nuoro big unrest: the whole population raised cries shouting su connottu! su connottu! against the sale of the State-owned grounds. After that a parliamentary inquiry commission headed at constituted a document of extraordinary importance for the knowledge of the topic. During a journey that lasted 18 days Sella, accompanied by the engineer Eugenio Marchese, manager of the mining district of Sardinia, visited the main mines and the metal-working factories of the island.
From his report the growing importance of the knowledge of the topic emerged within the Italian economy. In 1868-1869 in Sardinian mines there were 9,171 employees, almost three times as many as in 1860. In fact, following the extension to Sardinia of the mining act of 1840 of Piedmont and its following modification of 1859 in order to be more favourable for mining entrepreneurs, a swift development of researches and mining, an increase in production and employed hands was recorded. In 1870 the permits for research, that were 83 by the end of 1861 increased to 420 and the concessions from 16 to 32, The extracted mineral increased from 9,379,800 kilograms in 1860 to 127,924,600 kilograms in 1868 while its value got five times as high achieving in 1868-1869 the amount of £13.464.780.
From Sella's report it also comes out that, in order to ease the transportation of mineral to the landing points, up to 1870 the mining societies had built about 30 kilometers of railways and 1081 kilometers of land roads.
The steady development of mining industry led to the flow of technicians (engineers and geologists) and board employees from other regions of the kingdom. Because of the poor level of education and technical preparation of Sardinian hands, even the majority of qualified hands employed in mines came from the continent. Most of times the management of mining societies that operated on the island was set on criteria that could have been quietly defined as colonial; that is why very often these were confined to the exploitation of the richest parts of mined veins, transferring then out of Sardinia the mined material that was processed on plants located on the continent. The large proceeds coming from the exploitation of Sardinian mines were not invested again on the spot unless to ease the operation of the company. Sella's inquiry did not reveal the economic treatment inequities between Sardinian miners and those with a continental origin, not to mention the need to found a school for foundrymen and mining managers in Iglesias. The report ended with the recommendations that more capital should be invested to improve mining industry, first of all the emergency of building a road network between mines and of completing railways. The need of carrying out and developing an adequate telegraph communication network was also highlighted: Sella points out that the main mining companies demanded to be able to build, at their own expense, new telegraph lines in order to make communications faster. Such purpose was though made useless by the act that guaranteed the State the monopoly in the building of these important structures.
In 1872 the seat of the Sardinian Mining District was moved from Cagliari to Iglesias.
The year before, in 1871, the Italian mining activity had known the birth of a new industry. With the ultimate discovery and the beginning of mining, of silver-bearing vein of Saarabus, even in Italy the production of silvery minerals was commenced. A new production cycle lasting about forty years had begun.
Within a short period from fifteen million tons of mined minerals in 1871, the year in which the discovery of the Mine of Monte Narba was declared, 2000 average tons a year were achieved and produced within the ten years between 1880 and 1890, that Rolandi defined as "silvery ten-year-span-of-time", in which productions reached the value of two millions lire. From the three mines that were constituted on the ore body in 1871, they increased to ten within twenty years to decrease later in order to become only one when it came to close it for good. In Sarrabus it came to a real quest for silver: together with big societies, such as the Society of Lanusei and the society of Monteponi, many extemporised diggers of valuable metals demanded hundreds of permits to carry out mineral searches on the territories of the towns of Muravera, Villaputzu and, particularly, of San Vito. In 1851 the Genuese company "Unione Sulcis e Sarrabus" acquired the research permits in the area of Monte Narba, in the comune of San Vito. In 1885 the French engineer Leon Goüin founded in Genua the "Società Tacconis-Sarrabus" for the exploitation of the Tacconis mine. In 1888 Goüin himself constituted in Paris the "Societé des mines de Rio Ollastu". In its most flourishing period the ore body of the Sarrabus employed up to 1500 workers, distributed among the mines of Masaloni, Giovanni Bonu, Monte Narba, Per'Arba, Baccu Arrodas, Tuviois, S'erra e S'Ilixi and Nicola Secci. Just to have a more precise idea of the quality value of the silver ore body of the Sarrabus we can say that, while in the rest of the world the average silver revenue for 100 kilograms of lead was swaying around 200/300 grams, in the body of the Sarrabus was achieved an average of 1 kilogram for 100 kilograms. In Baccu Arrodas the assays were much higher.
In the 1930s there was extensive emigration from the mainland during the Fascist government when people from Veneto but also from Marche, Abruzzo and Sicily came to Sardinia to populate the new mining towns founded in the Sulcis-Iglesiente region such as Carbonia and Cortoghiana.
The Geomineral Park of Sardinia, founded in 1989, and supported by UNESCO, today preserves the ancient mines and the ex mining villages that are become examples of industrial archeology.
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