History
The Oroszlány coal basin occupies the northwestern foothills of the Vértes hills, an area of eocene brown coal deposits that were geologically explored from 1915 by deep drilling. The Magyar Általános Kőszénbánya Részvénytársulat (MÁK Rt.), which also operated the Tatabánya mines, held the initial concession. Coal extraction in the Oroszlány area began in 1937 under MÁK Rt., managed initially as an extension of the Tatabányai Szénbányák rather than as an independent entity. The Oroszlány basin adopted the Tatabánya shaft numbering convention, so the sequence of numbered shafts ran continuously across both basins. From 1 January 1957 the Oroszlányi Szénbányák Vállalat was constituted as an independent state enterprise.
The Állami Tervhivatal (State Planning Office) directed the construction of the XIX. and XX. aknák in Oroszlány and subsequently authorised the planning and construction of the XXI. akna. According to the OMBKE mine chronicle, the XXI. akna entered operation from 1 April 1961. The shaft and its associated mining unit became one of the most productive and technically progressive units in the Oroszlány basin during the 1960s.
The XXI. akna gained international recognition during this decade through its use of an English-Polish machine combination: Dobson brand hydraulically operated roof supports supplied by a British manufacturer, combined with a Polish-made drum shearer (maróhengeres fejtőgép) for longwall coal-cutting. This combination achieved production records that attracted professional visitors from across the COMECON countries. Czech, German, Soviet, Romanian, and Yugoslav mining engineers all attended the XXI. akna to observe the machinery in operation. The Dobson company's engineers visited regularly and in one instance telegraphed to Britain to report that the face had achieved an advance rate of 4.8 metres per day — a result described as world-class, comparable to the best-mechanised mines in Western countries at the time. When that advance rate was reached, the British engineers found even their characteristically reserved composure tested.
The Vértesinfo archive, citing contemporary press sources, confirms the XXI. akna set a Hungarian national production record and subsequently reached daily production in the associated longwall face of 1,132 tonnes on average across the month, representing an output comparable to international standards of the era.
The Oroszlányi Szénbányák's mines progressively closed from the 1990s onwards as brown coal became economically unviable following the end of the planned economy. The specific closure date of the XXI. akna is not established in the consulted sources, and no information on post-closure structure survival or heritage designation has been found for this shaft unit.