He then studied at the University of Marburg, where he wrote his first essay, Übersicht der geologischen Verhältnisse des Herzogtums Nassau (1847).

[1] In 1849 he became curator of the Natural History Museum at Wiesbaden, and began to study the Tertiary strata of the Mayence Basin, and also the Devonian fossils of the Rhenish provinces, on which he published elaborate memoirs.

[2] His great work Die Land- und Süsswasser-Conchylien der Vorwelt was published in 1870–1875.

His brother Guido Sandberger (1821–1869) was an authority on fossil cephalopoda, and together they published Die Versteinerungen des rheinischen Schichtensystems in Nassau (1850–1856).

[1] Adolf Sandberger, Fridolin's son, was a noted German musicologist and composer.