We have included a link to a short movie of this display in motion. (974kb)  Click the lead photo below to load the movie for viewing.  While you're waiting for the movie to load you can view larger versions of the two lower photos by clicking on them.

This specimen is a common opal limb cast (potch); while it has a nice base color there is no play of color.  It is a terrific example of total replacement by opal after wood.

take this link to view a cone showing contra luz color