1911 Census of England and Wales, General Report with Appendices, Table 39: " Males engaged in Mineral Extraction at each Census, 1851-1911, and Increase or Decrease per cent. in each Intercensal Period, 1881-1911".

MINERS IN 1851. 1861. 1871. 1881. 1891. 1901. 1911. Increase (+) or
Decrease (-)
per cent.
1881-
1891
1891-
1901
1901-
1911
Coal 183,389 246,613 268,091 378,664 513,843 640,989 874,304 35.7 24.7 36.4
Iron 19,380 20,626 20,931 25,879 18,158 17,008 22,299 -29.8 -6.3 31.1
Tin 12,911 14,314 10,617 10,499 9,670 6,577 7,125 -7.9 -32.0 8.3
Lead 20,030 18,552 14,563 11,022 5,723 4,375 2,968 -48.1 -23.6 -32.2
Copper 18,449 17,727 3,063 3,800 1,130 789 279 -70.3 -30.2 -64.6
Other or undefined Minerals (?) 8,039 39,130 2,061 2,401 2,457 1,784 - - -
  254,159 325,871 356,395 431,925 550,925 672,195 908,759 27.6 22.0 35.2
Owners, Agents, Managers, and
  Other Mine Service—
    Coal and Shale Mines 6,258 }4,482{ 10,346 }3,572 5,991 7,469{ 10,226 }67.7 24.7 46.6
    Other Metafliferous Mines ? 4,231 725
      Total 260,417 330,353 370,972 435,497 556,916 679,664 919,710 27.9 22.0 35.3