1726 |  | Ravensworth Ann Colliery also known as Team Colliery opened |
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1794 | | Washington Colliery opened before this date |
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c.1807 | | John Ashmour, born at Houghton-le-Spring. Deputy Overman |
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c.1809 | | Isabella, later wife of John Ashmour, born at Washington |
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c. 1811 | | William, brother of John Ashmour, born at Houghton-le-Spring. Onsetter |
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1820 | | Pittington Colliery sunk |
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1828 | | New Pit, Houghton-le-Spring opened before this date |
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c.1829 | | Simon Tate, first son of John Ashmour, born at Lamesley. Coalminer
Thomas, second son of John Ashmour, born at Houghton-le-Spring. Labourer |
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1831 | | Lady Alice’s Pit, Littletown opened
Henry, third son of John Ashmour, born at Lamesley. Coalminer |
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1833 | | Low Moorsley Colliery opened before this date |
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1834 | | Kelloe Winning Colliery opened |
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1835 | | Pelton Colliery opened
Elizabeth, first daughter of John Ashmour, born at Houghton-le-Spring |
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1836 | | Belmont Colliery opened |
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1837 | | Mary, second daughter of John Ashmour, born at Hallgarth |
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1838 | | Framwellgate Moor ‘Old Pit’ Colliery opened |
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1839 | | Sacriston Victoria Colliery opened
Nettlesworth Colliery opened |
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1840s | | Elvet Colliery opened? |
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1840s-60s | | Brasside Pit opened? |
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1840 | | Frankland Colliery opened
John, fourth son of John Ashmour, born at Hallgarth. Labourer |
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1842 | | Kibblesworth Colliery opened
Joseph, fifth son of John Ashmour, born at Kelloe. Scholar |
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1843 | | Isabella, third daughter of John Ashmour, born at Hallgarth |
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1845 | | William, sixth son of John Ashmour, born at Saint Margaret |
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1847 | | George, seventh son of John Ashmour, born at Witton Gilbert |
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1848 | | Robert, eight son of John Ashmour, born at Saint Margaret |
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1850 | | Ravensworth Shop Colliery also known as Allerdean Colliery
Matthew, ninth son of John Ashmour, born at Chester-le-Street |
