The papers cover the period 1951-1998. Preponderantly, however, they date from Cox's time at Oxford from 1972 to his death. There are no direct remaining records of his work at Edinburgh, and only his doctoral thesis commemorates the Leeds period.
Biographical and personal material includes Cox's incomplete autobiographical account of his career, his doctoral thesis at Leeds, and correspondence showing his concern with the life, work and gardens of Jesus College, Oxford where he was Senior Research Fellow and Garden Master. The account of his death and the many tributes received from school friends, research students and senior colleagues give insights into personality and scholarly achievements. There are records of Cox's research on volcanic basalts in diverse regions of the globe, including correspondence, research proposals, plans and results, data, analyses, calculations, and drafts for papers. The Oxford University Department of Earth Sciences is represented by teaching and lecture material, which follows the development of Cox's research interests and methodology and the material for student field trips, his own introductory information for participants, and the detailed maps provided which reflect the importance he attached to accurate geological mapping.
There is a scanty record of Cox's lectures and conferences, since he virtually never wrote or delivered a prepared text. The papers are also deficient in drafts or manuscripts for Cox's own publications, but give quite a full picture of his extensive involvement in editorial and refereeing work, including a long association with the Journal of Petrology of which he was Managing Editor from 1972 and where many of his papers were published. Similarly, societies and organisations material is not extensive, as Cox did not actively seek out participation in the public life of science or in general advisory work. There is, however, documentation of his Chairmanship of the Scientific Advisory Board of GEOMAR (the Research Centre for Marine Geosciences at Kiel) and some of his appointments and work at the Royal Society. Cox's correspondence often provides a useful complement to the research material, being almost entirely concerned with research and publications, though it is mainly confined to the Oxford period. Non-textual material comprises transparencies, maps, diagrams and photographs, the latter including a famous photograph of the Deccan Traps which was frequently borrowed and reproduced. Cox was a talented amateur water-colourist and several of the maps and diagrams show his skill.