Mona Mine Papers

Scope and Content

Comprises material relating to Mona Mine Company: 

  • Correspondence between the Earl of Uxbridge and Thomas Williams, 1787-1800
  • Letters from S. Taylor to John Price and William Cary, mainly about the Stanley enterprise near Liverpool, 1798-1800
  • Photocopies of copper accounts, Parys Mine, 1782-1793 and Mona Mine, 1786-1793
  • Accounts, 1782-1800
  • Ledgers, Mona Mine Company and Mona Smelting Works, etc., 1818-1865
  • List of arrears due to the Mona Mine Company with a rental of their estate, 1802-1812

Administrative / Biographical History

Copper was rediscovered at Parys Mountain between 1761 and 1768 on the estate of Sir Nicholas Bayly (1707-1782) of Plas Newydd, who owned Cerrig-y-bleiddia Farm, on the east of the hill and also had a share in Parys Farm on the western part. A legal dispute between Sir Nicholas Bayly and the other owners of Parys Farm resulted in the engagement of solicitor Thomas Williams (1737-1802) of Llanidan. In 1778 Sir Nicholas Bayly leased his share in the Parys Mine to a Macclesfield company in which Thomas Williams was partner. By 1785, the lease had run out and Sir Nicholas' son and heir, Henry Bayly, Earl of Uxbridge (1744-1812) went into partnership with Thomas Williams to form the Mona Mine Company. Production began to decline around 1850 although it continued until 1883 and ore recovery carried on into the twentieth century on a small scale.


Material was received on separate occasions, arranged in chronological order and incorporated into the General Collection of Bangor Manuscripts .

Conditions Governing Access

Open to all users


Description compiled by Anne Lenaghan, August 2002.

Other Finding Aids

Item level word-processed list is available at the Archives Department, University of Wales, Bangor. Reference numbers: General Collection of Bangor Manuscripts: 880, 3010-3032, 15365-15366

Conditions Governing Use

Usual copyright conditions apply. Reprographics are made at the discretion of the Archivist.

Related Material

Also held at the Archives Department of the University of Wales, Bangor are the Mona Mine Records (Plas Newydd Papers) and the Peckover, Burrill and Owen Papers. Collection level descriptions are available on the Archives Hub. Other related material is held at the University including reference numbers General Collection of Bangor Manuscripts: 15161, 27537, 33223, 33977.

Additional Information

Originals of photocopies of copper accounts, Parys Mine, 1782-1793 and Mona Mine, 1786-1793 (reference numbers: General Collection of Bangor Manuscripts: 15365-15366) held at the Library of the University of Wales, Swansea.