Mood: don't ask
Topic: geology et al
The iron range is of great social and cultural interest as well as geological, esp. for rock collectors, but that is not the focus of this blog. As someone whose grandfather was once known as "the binghamite king" and as someone who owns or has access to several ton of the algal material of the upper cherty division of the Biwabik formation, part of the Mesabi range, I am very interested in this.
These are mostly open pit mines rather than underground, because the deposits are just under the glacial drift. (An exception to this has been at Ely). The extraction of high grade ore is not as profitable as it once was. Taconite is another name for the lower grade iron bearing rocks.
A complex series of events over the eons resulted in deposits of the high grade ore that for the longest time made this area the greatest iron producing area in the world. Mining was begun in 1884. I am eager to see what a more recent books says about this subject.
I sell drill cores at my shop.
Hoffs Rock Shop