Surviving iron and timber drainage shaft structure of the Mina de São Domingos, a major copper-pyrite complex now a classified heritage site with active tourism.
The Malacate (São Domingos) is a surviving industrial structure forming part of the extensive former copper-pyrite mining complex of the Mina de São Domingos, located at the hamlet of Mina de São Domingos in the parish of Corte do Pinto, municipality of Mértola, district of Beja. The mine lies within the Iberian Pyrite Belt, one of Europe's principal metallogenic provinces. The Malacate, specifically known as Poço Malacate nº 6, was built of iron and timber and served to drain groundwater from the 150-metre level of the open-pit workings, operating through a large electric turbine that raised water in enormous buckets to a surface reservoir.
Modern mining at São Domingos was conducted by the British firm Mason & Barry from 1858 until 1966, during which period over 20 million tonnes of ore were extracted. Following closure the complex fell into ruin, but has since been partially preserved as a Conjunto de Interesse Público since 2013 and is managed by the Fundação Serrão Martins. The Malacate forms part of the Industrial Circuit visitor route now promoted at the site.
The deposit at Mina de São Domingos was exploited from at least the Bronze Age and subsequently by Phoenician, Carthaginian, Roman, and Islamic workings, though the modern industrial significance of the site dates from the mid-nineteenth century. The first registration of the modern concession was made in June 1854 in the name of Nicolau Biava, acting on behalf of the French mining entrepreneur Ernest Deligny. In March 1855 the rights were transferred to Deligny and partners, who established the company La Sabina to exploit the Portuguese pyrite deposits.
In May 1858 La Sabina leased the working of the mine to the British firm Mason & Barry, which would go on to extract ore from São Domingos for over a century. The deposit is a single mass of copper-bearing pyrite distributed between the surface and 420 metres depth, with average grades of approximately 1.25% copper, 1% lead, 2% zinc, and 45–48% sulphur, alongside iron and arsenic. Principal commodities extracted during the modern period were copper and sulphur.
The ore was processed at the Achada do Gamo complex and the Moitinha crushing centre, and transported by one of Portugal's first private railways to the river port at Pomarão on the Guadiana, from where it was shipped abroad. The mine was the largest mining operation in Portugal until the 1930s, employing a continuous workforce of over 1,000 workers through much of its active life. The complex included infrastructure well beyond that typical of Portuguese industrial sites of the period: a hospital, a theatre, a church, a Protestant cemetery, workshops where locomotives were built and maintained, and a power station that became the first in the Alentejo region.
The Malacate — Poço Malacate nº 6 — was a dewatering shaft structure of iron and timber construction. Its function was to drain water from the 150-metre level of the corta (the open-pit workings), keeping the excavation sufficiently dry for continued extraction. Water was raised from depth in large buckets driven by a powerful electric turbine in a balanced reciprocating motion, then channelled into a surface reservoir from which it flowed by canal to the Moitinha crushing centre and the Achada do Gamo metallurgical complex.
The structure's name derives from the Spanish and Portuguese term malacate, broadly denoting a whim or hoisting device historically powered by animal or mechanical means. Mason & Barry's operations continued until 1966, when ore extraction ceased. The company declared bankruptcy in June 1968, with debts to workers and the social security system.
La Sabina, which had maintained a landlord relationship with Mason & Barry since the nineteenth century, recovered the property under the terms of their lease. The mining concession of São Domingos expired in 1984. Following closure the entire complex entered a prolonged period of abandonment and environmental deterioration; the ore extraction left significant acidic drainage affecting the surrounding landscape and watercourses.
In 2004 the Câmara Municipal de Mértola and La Sabina established the Fundação Serrão Martins as a non-profit body to conserve, valorise, and promote the heritage of the Mina de São Domingos and support local development. In the same year a monument to the miners was inaugurated in the village. On 3 June 2013 the mining complex of the Mina de São Domingos was classified as a Conjunto de Interesse Público under Portuguese law.
A state environmental remediation programme coordinated by the Empresa de Desenvolvimento Mineiro began in 2016, budgeted at approximately 20 million euros with European Community funding, covering drainage control, waste confinement, acid water treatment, and eventual heritage and tourism valorisation. The Malacate now forms a stop on the Industrial Circuit visitor route at the site, alongside the Corta da Mina, Cais do Minério, the railway workshops, Moitinha station, and the Achada do Gamo complex. In 2021 the Malacate also gave its name to a multidisciplinary arts residency project, funded under the European Economic Area agreement, organised at the Mina de São Domingos.
In 2023 a group of German investors acquired the land of the former complex with plans to develop solar, wind, and green hydrogen energy installations.