He was born in Talca on 15 June 1905, the son of José Martones and Rosa Quezada. He studied at the Public Superior School No. 1 and the Superior School No. 3 of Talca, later entering the Talca Commercial Institute in 1917, graduating as an accountant in 1919. In 1920, he studied metallurgy at the School of Arts and Crafts of the Universidad Técnica del Estado.
He married Elena del Rosario Morales Soto in May 1926, with whom he had three children: Humberto, Dantón, and Mirtho. In 1983 he remarried Edith Alicia Salomón Lúzquez.
Martones began his working life as a mechanic at the Libertad Foundry for two years, followed by two years at the Fábricas y Maestranzas del Ejército (FAMAE). He later joined Cristalerías Yungay.
He served as Head of the Unemployment Relief Commission (1933–1937), Head of the Relief Directorate for Earthquake Victims (1939), and Secretary-General of the Commissariat of Supplies and Prices (1940–1945). He also owned the Metalúrgica del Pacífico in Santiago.
He was active in labor movements, serving as:
- Secretary-General of the Union of Metalworkers (1921–1927)
- Secretary-Treasurer of the Industrial Union of the Yungay Glass Factory (1929–1930)
- Secretary of the Industrial Union of Weir Scott & Co.
- President of the Chilean Workers’ Social Congress (1929)
Martones’s political path began in the anarchist movement in 1922, later joining the Republican Confederation of Civic Action (CRAC), where he served as vice president in 1930.
He joined the Democratic Party between 1932 and 1948, then the Democratic People’s Party until 1958, and finally the Socialist Party of Chile from 1958 onward. He was also the electoral chief of the Frente de Acción Popular (FRAP) and campaign manager for Salvador Allende’s 1958 presidential run.
He was first elected Deputy for Santiago (1930–1932) as a representative of the CRAC. He served on the Committees on Public Education and Labor and Social Welfare. His term ended with the dissolution of Congress after the June 1932 revolution.
Later, he was elected Deputy again for Santiago (1949–1953), serving on the Committees on Finance, National Defense, and Economy and Commerce. He also took part in special commissions that investigated the National Asylum and the operations of FAMAE (1949–1950).
In 1953, Martones was elected Senator for the 7th Provincial District (Ñuble, Concepción, and Arauco) for the 1953–1961 term. He served on the Committees on Finance and Budgets and Foreign Relations, and as substitute on the Committee on Public Works and Transportation. He was a member of the Joint Budget Commission in 1953–1954, 1959, and 1960.
As legislator, he co-sponsored the law establishing a monument in honor of Father Alberto Hurtado Cruchaga (Law No. 13.594, 24 October 1959).
Appointed by President Carlos Ibáñez del Campo, Martones served as Minister of Public Works and Transportation from 3 November 1952 to 5 March 1953.
He was Chile’s delegate and presiding officer at the Fifth Session of the ECLAC in Rio de Janeiro (1953), and was appointed Director of the World Peace Council in Colombo, Ceylon (1956).
He was a member of the Club F.B. Ferrobadminton, the Centro de Hijos de Talca, and the Sociedad Lorenzo Arenas de Concepción.
He died in Temuco on 29 January 1999, aged 94.