In keeping with the Library's name and its motto – Viris ferrum donantibus – the original collection focus was on literature about iron and steel, whether mining or production. In the course of time, the focus has expanded to include selected fields of the history of technology along with allied disciplines (history of the natural sciences, archeometallurgy, industrial and economic history, industrial heritage, etc.). Worldwide, there are not many specialist libraries in this field with holdings of comparable depth, breadth and completeness. In the wake of developments within the three divisions of Georg Fischer Ltd, new, additional collection interests are taking shape: In future, greater emphasis will be placed particularly on plastics and their history.
The core of the collections is a large number of old (bibliophile) books and prints and a much smaller number of manuscripts. These valuable historical holdings were acquired at the time the Library was established or shortly thereafter and are currently being added to by selective acquisition of antiquarian items. The basic principle applying to all collection interests is that the Library acquires both historical items and new (scholarly historical) research literature. There is no clear demarcation line between historical and current holdings since this will depend on the thrust of the research. Literature that is not historically oriented is acquired in some areas such as foundry technology, iron metallurgy and plastics technology. The holdings are arranged according to the Iron Library's own classification system. The current system (see link on the right side) and the article on the Iron Library in Handbuch der historischen Buchbestände in der Schweiz [Historical Book Holdings in Switzerland] (updated in 2009, see link on the right side) give the reader a good idea of the Iron Library's collection interests.