1135 |  | First mention of lead mining in Durham. Charter of King Stephen granting ‘the right to mine for silver’ to his nephew, Hugh De Puiset, Bishop of Durham. |
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1401 |  | First mention of mining at Blackdene – leased to Roger Thornton, a Newcastle merchant. He was granted permission to work a mine at “Aldwoodclough” for 12 years. |
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1680 |  | Mines at West Blackdene mentioned in the court battle between Humphrey Whorton, Moormaster and the Rector of Stanhope over unpaid tithe ore. |
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1696 |  | William Blackett takes over as Moormaster for Weardale. A position his family holds for nearly 200 years. |
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1720 |  | 22 bargains taken to work veins in Blackdene mine. |
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1818
to
1876 |  | Production figures for Blackdene and Elmford mine – 26,581 tons of lead concentrates. |
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1863
to
1873 |  | New Selding Level driven from Blackdene mine to drain the lower reaches of the adjacent Sedling Mine. |
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1883 |  | June – Weardale Lead Company formed, taking over leases from Beaumont Co, but not considered to be re-opened for lead. |
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1905
to
1906 |  | Production figures for Blackdene Mine under Weardale Lead Co.
Lead – 5 tons
Fluorspar – 43 tons |
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1949 |  | United Steel Co Ltd acquire Blackdene Mine and put in hand a vigorous exploration and development plan. |
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1953 |  | Blackdene dressing plant no 1 built to process ore from the mine – consisting of jigging machines and shaking tables.
Output 6,500 tons per year. |
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1965
to
1968 |  | New incline 458 metres long at an incline of 1 in 7. Driven to access deeper reserves. |
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1967 |  | Nationalisation of the steel industry sees Blackdene Mine pass to British Steel Corporation, becoming one of the principal fluorspar producers. |
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1978
to
1980 |  | Blackdene Flotation and Briquetting Plant built by N>E>I> International of Derby at a cost of two and a quarter million pounds. It had a designed capactiy of 100,000 tons per year. |
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April 1981 |  | Blackdene Mine ceases production. Ore for new processing plant coming from Grove Rake and White Heaps until 1981. |
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May
1982 |  | British Steel Co. sold its interests in Weardale to Weardale Mining and Processing Ltd. A subsidiary of the Minworth Group. |
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1991 |  | Minworth Group put into receivership. Machinery removed and sent to Morocco to process Barite. |
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1997 |  | Blackdene Mine and plant Site Cleared. |