Of or pertaining to certain non fossiliferous rocks on the borders of Lake Huron which are supposed to correspond in time to the latter part of the Archaeligan age
- Of or related to specific non-fossiliferous stones on the borders of Lake Huron, which are likely to correspond over time to the second an element of the Archaean age.
(a.) Of or regarding specific non-fossiliferous stones on the boundaries of Lake Huron, which are likely to correspond in time into second area of the Archaean age.
Lake Superior lies in a deep rift in rocks principally of Archean and Cambrian age, of the Laurentian, Huronian and Keweenaw formations, rich in minerals that have been extensively worked.