Deeds and papers relating to Penucha, Aberchwiler, Denbighshire, as well as other properties in Denbighsire and Flintshire, 1795-1824; miscellaneous accounts and papers, 1787-1842; correspondence of Thomas Jones, 1800-[c. 1820]; testamentary papers of Thomas Jones, [c.1820]-[c. 1843]; testamentary papers of Mrs Elizabeth Jones, 1804-1824; letters and papers of Mrs Mary Jones, 1820-1837; legal papers, 1818-1823; transcripts, mainly of papers relating to the settlement of Elizabeth Jones' estate, 1810-1837; notes concerning Thomas Jones, [c. 1902]-1957; copies of books and tracts by Thomas Jones and books and articles about him by Idwal Jones and others, 1789-1974; illustrations, [19th century]; miscellaneous [20th Century].
Apart from deeds relating to Penucha (the property inherited by Thomas Jones from his father) most of the manuscript material in the collection comprises family correspondence and papers. A significant proportion relates to the settlement of his first wife's estate, and the consequent long running dispute with Edward Jones of Mold, her brother.
In the collection are a number of early books and tracts written and /or published by Thomas Jones.
After Thomas Jones' death, further papers were added relating to his and his wives' estates, and to Sir J. Herbert Lewis and his family. Professor Idwal Jones' biographical notes on Thomas Jones were also added.