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That's pretty much what a frown is, concave edge profile. When compared to a straightedge, the toe and the heel (ends of the razors) will come to contact with the straightedge, but the middle won't....

There's seems to be some uneven honewear and looks like somebody took sandpaper to it to make it look shinier. There might also be some frown on that as well. I hope you get a good blade out of it.
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