FMF Minerals Gallery

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This appeared inside a piece of septarian mudstone I chopped up, I have absolutely no idea what it is/was, the stone is from Carboniferous strata, an area called "The Caton Shales" in the north west of England,near my home. Ive recovered maybe 200 or so specimens from this area but this is unlike any of the others. Im tempted to cut it lengthways so as to see another view which may yield further clues. size 135 x 40 mm (Author: nurbo)