Petrus Joannes Jansen died in the Japanese concentration camp at Tjideng, Batavia, on February 11th, 1945, at the age of about 72.
He received his professional training at Delft University, Holland, graduating as mining engineer in 1899. He was engaged from 1900 to 1908 on Government prospecting work in the Dutch East Indies, first at Atjeh in North-West Sumatra, and for some three years was engineer in charge of prospecting and developing some gold-bearing reefs in the Benkoelen district. In May, 1908, he was appointed general manager of the Lebong Soelit gold mine of Mijnbouw Maatschappij Ketahoen in Sumatra, and two years later left to become, in turn, general manager of Simau gold and silver mines, Lebong Tandai, and Redjang Lebong gold and silver mine, Moeara Aman, Sumatra.
In 1925 he was appointed consulting engineer to various gold mining companies in the Dutch East Indies, including the Simau, Moeara Sibongi, Zuid Bantam, and Nederlandsch Nieuw Guinea mining companies. During the years 1925 to 1938 he travelled extensively, reporting on mines in Europe, the United States, Australia, New Guinea, and Papua, and for his services as a mining engineer and for public work in Sumatra, Mr. Jansen was awarded the Order of Orange Nassau, by the Queen of Holland.
He was elected to Membership of the Institution in 1910.
Vol. 56, Trans IMM 1946-47, p.619.