Lloyd Montgomery Pidgeon

Lloyd Montgomery Pidgeon, a chemist who pioneered a process for producing magnesium, has died. He was 96.

The son of a minister, Pidgeon was born in Markham, Ont., in 1906. He obtained a chemistry degree from the University of Manitoba in 1925 and went on to complete his graduate studies at McGill University, obtaining a master’s degree in 1927 and a PhD in 1929. He spent several years at Oxford before joining the National Research Council of Canada in 1931 to work on electrochemical research. His work there led to the development of a process by which high-purity magnesium is produced. However, the process was costly and inefficient, and commercial production was deemed impractical.

Pidgeon later found a solution in dolomite, a sedimentary rock. Although its high magnesium content was difficult to remove through conventional smelting, Pidgeon found a way to extract it by combining the dolomite with ferrosilicon. The process that now bears his name involves heating the mixture in a vacuum and capturing and condensing the resulting magnesium vapour.

Pidgeon’s work soon attracted the attention of Thayer Lindsay, R.J. Jowsey and W.M. Segsworth, who later raised money for Pidgeon to build a pilot plant to test his process on a larger scale. The plant was built near Renfrew, Ont.

In 1941, Pidgeon joined Dominion Magnesium as head of research. The company was formed to produce magnesium at a time when demand for the strong, light-weight metal was at an all-time high. Six plants in North America began producing magnesium according to the “Pidgeon Process”. The metal was then used in the manufacture of airplane parts for the Allied effort during the Second World War.

Two years later, Pidgeon was appointed to head the metallurgical engineering department at the University of Toronto. He remained an academic until his retirement in 1969, though he also acted as a consultant to the industry and helped develop processing technology for calcium and strontium. As a result of this work, Canada remains one of the top producers of these alkaline metals.

Pidgeon was named to the Order of the British Empire in 1946 and as an Officer of the Order of Canada in 1996. He was inducted to the Canadian Mining Hall of Fame in 1996.

He is survived by daughter Ruth, son Edward, four grandchildren and one great-grandson.