|Obverse: HCH EMANUEL MERCK 1794-1855 DARMSTADT
Reverse: FVR VIERZIG JÄHRIGE TREVE MITARBEIT
Merck was founded in Darmstadt, Germany, in 1668 by Jacob Merck. At the origin, it was an apothecary shop named Engel-Apotheke (the Angel pharmacy). Starting in 1827, it turned to a more industrial environment under Emanuel Merck who worked on alcaloids. In 1850, with his sons, E. Merck founded the eponymous company.
Reference: Münzkabinett der Staatlichen Museen zu Berlin