David J. Williams was an associate of the Royal School of Mines (London) who arrived on the Witwatersrand in or before 1897. In that year he became a member of the Chemical and Metallurgical Society of South Africa and remained a member when it was revived as the Chemical, Metallurgical and Mining Society of South Africa in 1902, after the Anglo-Boer War (1899-1902). During 1904/5 he served as a member of the society's council. At that time he worked as a consulting mining engineer to the African Claim and Land Company, Johannesburg.
In May 1897 he read a paper before the society on "The estimation of lead in slags and other by-products", which was published in its Proceedings (Vol. 2, pp. 61-65). His second paper, "Notes on mine sampling of the Main Reef series", was delivered in October 1902 (Proceedings, Vol. 3, p. 160). In 1906 he was a member of the South African Association for the Advancement of Science.