- 1864 – 1879 : Thomas Charlton and Company
- 1880 – 1906 : Sir Bernard Samuelson and Company
- 1864 – Drift working start near what is now Charltons village
- 1868 – Mine hits trouble as main seam is ‘washed out’
- 1880 – Samuelson takes over and sinks 286ft shaft at southern extremity
- 1890 – Samuelson takes over Spa Wood with connections underground, so shafts are only needed for ventilation.
Catalogue of Cleveland Ironstone Mine (Peter Tuffs, Cleveland Ironstone Series, 2003)
Guisborough District Mines (Simon Chapman, Cleveland Ironstone Series, 2001)