Fredrik Johan Wiik, also known as F.J. Wiik (December 16, 1839 in Helsinki - June 15, 1909 in Helsinki) was a Finnish geologist and mineralogist; in 1877, he was named the first professor of geology and mineralogy at the Imperial Alexander University of Finland [1], where his students included Jakob Sederholm.[2] He was also the first scientist in Finland to use a petrographic microscope.
Wiik died in 1909, on a geological expedition; his body was found clutching his geologist's hammer.[3]
The mineral wiikite is named for him.