Pumpkin Stone

• Pumpkin Stone
  Locality: Nakano, Seidan-cho, Mihara-gun, Awaji-shima, Hyogo-ken, Japan
  
  This stone is called the “Pumpkin Stone”, because its wavy surface reminds us of vertical smooth grooves of pumpkins. Of course, this is not a fossil of a pumpkin. It is a fossil of ammonite.
  It might be very different from your image of ammonite, but you know, so many ammonite varieties had existed. This kind of ammonite was formerly called “abnormally coiled”. As to this specimen, the coiled shell had become loose and three-dimensional.