John Charles Tonkin died in Argentina, on 7th August, 1948, at the age of 61, after suffering for some time with heart trouble.
He received his technical training from 1905 to 1908 at Birkbeck College, London, and the Camborne School of Mines. In June, 1908, he took up the appointment of sampler to the Falmouth Consolidated Mines, Ltd., and from 1909 to 1910 was employed by the St. Ives Consolidated Mines, Ltd. He then worked for a year as assistant manager to the National Refractory Minerals Process, Ltd., and for a few months held a similar position with West Kitty Mines, Ltd. During 1911 he was in charge of the five mills of the Falmouth Consolidated, St. Ives Consolidated and West Kitty mines, leaving England for Rhodesia in September, 1911, as manager of Rhodesian Refractory Minerals Process, Ltd., at Gadzema, where he carried out experimental work on gold ores.
In 1913 Mr. Tonkin went to Bolivia, and for four years was engaged in private mining, inspecting and working on his own and rented properties. In 1917 he was appointed mine superintendent to the Cia Huanchaca de Bolivia, and later in that year was appointed chief engineer to Cia Minera y Agricola Oploca do Bolivia, leaving in September, 1918, to return to England for war service.
From 1919 to 1920 he was employed as manager of the Tutusi, Portugalete and Chosonia sections of Ciu Minera y Agricola Oploca de Bolivia, before receiving the appointment of general manager of those sections, and from 1922 to 1924 was also acting general manager of the company. In November, 1924, he was made general manager, and held this position until 1935. In 1936 he was appointed general manager of Sociedad Minera Pirquitas, Picchetti y Cie, in Argentina, but six years later he relinquished this position owing to loss of vision. He set up in private practice in 1942 as a consulting mining engineer with headquarters in Buenos Aires, but in 1946 heart trouble forced him to retire.
Mr. Tonkin was elected to Membership of the Institution in 1927.
Vol. 58, Trans IMM 1948-49, p.595
