The Sioux quartzite is exposed in this state only in the extreme northwestern corner of Lyon County. Other and greater exposures however are found in the adjacent parts of South Dakota.
Proceedings of the Iowa Academy of Sciences
©1896 Iowa Academy of Science, Inc.
"The Flora of the Sioux Quartzite in Iowa,"
Proceedings of the Iowa Academy of Science, 4(1), 72-77.
Available at: https://scholarworks.uni.edu/pias/vol4/iss1/15