Look at the next four images and imagine how the entire fossil might look.
The first two images represent slices down the center of the original fossil, as if the fossil was split in half. Both show the spiral shape of a thin-walled (dark) shell. The shell wall is crinkled. You can see that the interior of the fossil sometimes contains chambers. The third image is a slice that was taken at an angle through a fragment of the fossil. The whole spiral shape is not evident, but you can still tell that this is part of a spiral shell, and that the outer wall of the shell is crinkled. The last image is a slice through the side of the fossil, such that you are looking down on the top of the fossil. This slice is at a right angle to the top three images. This view does not show a spiral, but does show chambers. Can you guess the original shape of this fossil from these pictures?
Skip fossils 2, 3, and 4. Go directly to the fact sheet to identify the fossils. http://www.uky.edu/KGS/education/YoungFossils-11.pdf
Leave this site and link to more information about modern animals with this type of shell, as well as a fossil FAQ sheet about this type of fossil. http://www.dal.ca/~ceph/TCP/Npompil.html