This Jack Knife Clam Fossil is so amazing!! This was found by my Father-In-law in the Miami River over 50 years ago. They are absolutely beautiful and would make a great addition to any collection! One measures 3″ long. The longer one measures 4 1/4″ Long.  They are very delicate.  I gladly combine shipping and I have lots of sea shells up for sale and fossils. Thanks for stopping by!