Jona was the first of the three sons of Giacomo Iona and Erminia Liebmann from Trieste. After studying at the Royal School of Trieste, in 1905 he enrolled in the faculty of architecture of the Polytechnic of Milan, graduating in 1909 and starting shortly after an apprenticeship at the studio of the architect Francesco Pestagalli.

In 1913, in Milan he created the funeral aedia Ascoli in the monumental cemetery, then in 1920-21 he collaborated with the engineer Antonio Bruna for the construction site of the national theater in viale XX settembre in Trieste and, subsequently, with the construction company Ing. C. Bressan, arch. G. Luzzato & C in Gorizia.

The predilection for the use of historical styles, in particular the Italian Renaissance, an expression of the national style, re-emerges in the competition projects for the Banco headquarters in Rome (1922) and the INAIL headquarters in Trieste (1924). This interest is subsequently developed in Trieste according to two main strands: the first includes isolated villas, simply declined according to rustic and Mediterranean suggestions; the second involves the interventions of large residential complexes for the Municipal Institute of minimal houses (ICAM), with monumental accents. Especially in the villas, the memory of Amalfi architecture resurfaces, which he analyzed together with that of the Aost Valley through views collected and published around 1920.

In 1930 he began working in contact with the engineer Paolo Grassi of the municipal technical office. His strong interest in the new rationalist architecture is then expressed, which grows with his commitment within the Public Works Office of the Municipality of Trieste, formalized starting in 1932. Engineer Grassi involves him in the drafting of the master plan for the Old Town and subsequently for the entire city, and entrusts him with the design of the planned views on new road axes and the main monumental nodes.

He was also commissioned to design some important public buildings, such as the market square in Viale Carducci (1935-1936), the so-called "New Market" or the "Covered Market",[3]which was then inaugurated on October 28 with the intervention of the Duke of Aosta. In this case, however, the reorganization measures planned for the site by Jonah, and connected with a new urban and development plan, were not implemented in their entirety and the Covered Market was therefore an urban resting space without being a suitable response to the urban issues of meaning and orientation of the place raised by the demolition of some condominiums that had become necessary for the construction of the work. Other projects were then the tram waiting stations (1933-1934) and the project for the luminous fountain of Montuzza (1937) which, since Jona will be affected by the racial laws, will then be carried out by fellow engineer Vittorio Privileggi in 1938.

After the war he followed the construction of some municipal economic houses and designed the school complex in San Sabba in Trieste (1947), then consolidating his role within the technical office until 1956. Jona's last relevant work as an independent designer is the project with Ramiro Meng for the INA-Casa di Chiadino-Rozzol district in Trieste (1957-1961).