FMF - Friends of Minerals Forum, discussion and message board

[John Jaszczak]

Some excellent specimens of crystallized naive copper were collected by Bob Barron in Lake Superior's Great Sand Bay north of Eagle Harbor, Michigan. Tom Rosemeyer wrote a nice article about it in Rocks and Minerals vol. 84 (2009).

[Bob Harman]

In the sedimentary areas of the US Midwest there are several localities where MILLERITE (NiS) can reliably be found. Perhaps the best known locality is Hall's Gap Kentucky. The Harrodsburg road cuts in Monroe County Indiana is another well known locality as are several sites in the Keokuk geode area of Iowa, Illinois, and Missouri. Less well known is the Wallace Stone Quarry (Bayport Quarry) in Bayport Michigan, Huron County. This quarry is also one of very few Michigan geode sites in general.

The Michigan geodes, like those at the Hall's Gap locality, tend to be small and very small and chock full of intertwined fine silvery wires of the millerite. Here are 3 examples from the 1980s and 1990s, 1.8 cm - 2.4 cm. BOB