Gadolinia, designed by Woldemar Baeckman and Helmer Löfström, was inaugurated on 21 November 1969. Baeckman had previously designed the extension of the Book Tower (1956–58), the School of Business (1963) and the Sibelius Museum (1968). Gadolinia was the largest new building the Foundation had constructed up to that point.

The building consisted of two main parts: a six-storey laboratory wing along Porthansgatan and a lower box-shaped structure that opened toward the inner courtyard. That section housed the student restaurant, featuring large glass windows facing the courtyard. The two parts were connected by a shared ground level with basement floors beneath. The main entrance was situated on the ground level, accessible from the courtyard side facing Biskopsgatan. This level contained the entrance, caretaker’s room, lobby and several lecture halls.

The ground level extended all the way toward Åbo Akademi and was arranged as storage space two floors underground, known as Maxilagret. Workshops and laboratories were located below street level along Porthansgatan, and one floor farther down toward Henriksgatan the accelerator was placed.

The building housed several Åbo Akademi departments. Originally it contained the Department of Physics, the Department of Physical Chemistry, Biology, Biochemistry, as well as technical facilities and laboratories. In later years only Chemistry and Physics remained in the building. Academic activities moved out when the new departmental building Aurum was completed in 2021.