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Flintsteel/Nassau Mine was one of several sites for "Datolite Day" collecting
trips during the Keweenaw Weeks hosted by Michigan Tech University each
August. Already many datolites have been found. I don't know if any more
datolites can be still found there, but it's just a matter of digging to
find any and I haven't been there mainly due to fees that I couldn't afford
(I want to go there!). This mine is very well known for its datolites with
very bright red color with white rims and the datolites also have been
found in pink, orange, yellow and possibly lavendar colors.
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