Kenneth Henderson Jack FRS (12 October 1918—28 January 2013) was a British chemist whose career involved the application of X-ray crystallography to the field of materials science.

Kenneth Henderson Jack was born on 12 October 1918 at his grandmother's flat in Coburg Street, North Shields.

After a brief spell in teaching – a requirement of his scholarship – he was directed into war work at the Chemical Defence Research Establishment, Sutton Oak,[3] before the Professor of Inorganic and Physical Chemistry, H. L. Riley[4] brought him back to Newcastle in October 1941.

Jack's work in this field came to the notice of Sir Charles Goodeve, the first director of the British Iron and Steel Research Association (BISRA), who appointed him as a Senior Scientific Officer in 1945.

On 11 August he and his family arrived in New York on the Mauretania, and Jack started at the 500-strong research facility, in charge of the X-ray lab.

He and his team developed a way ok making a much-improved version of the firm's main product: a fused quartz with the brand name Spectrosil.

The professor of metallurgy at Jing's College asked Kenneth Jack, in 1963, if he was interested in a recently established readership there.

His lines of research includes a focus on silicon nitride (Si3N4) and its development into more complex Si-Al-O-N structures; the discovery of Guinier–Preston (GP) zones in Fe-Mo-N.

The work of the growing Wolfson group “became better and better known [and] there were many invitations to give lectures overseas in Europe, the USA, Japan, India, Pakistan and China.

He spent 1969–1970 as an ICI postdoctoral fellow in his father's research group at Newcastle, before being appointed Lecturer in the Metallurgy Department at Leeds University.