Due to the mixed management of the MBCN it is necessary to distinguish between the collections that are owned by the council, those that belong to the MBCN Association and those that are permanently housed. All of them receive the same treatment from the Museum and are governed by the same rules:
The Guillem Colom Collection This is made up of a large number of micropaleontological preparations (approx. 20,000), especially foraminiferas from several locations but mainly from Balearic sites. There is also a representation of present-day foraminiferas, primarily from the Mediterranean, as well as samples prepared for study and a collection of fine lamina preparations... [+]
The Juan Bauzá Collection This is made up of a large number of fossil samples (approx. 30,000) from the Balearics and other areas. The Balearic fossil register is represented in the collection, from the Carboniferous Period up to the Quaternary with special attention to fish fossils... [+]
The William Waldren Collection
This special collection consists of a significant number of fossil remains of Myotragus balearicus Bate, an artiodactyl native to the Balearics whose extinction coincided with the appearance of the human population on the archipelago.
The General Collection This collection brings together all the materials generated by the Museum since its foundation, and also from collections donated or housed by independent researchers or other people or institutions... [+]