5.6" Fossil Capelin Fish (Mallotus) Nodule Half - Ontario

This is a fossil Capelin fish of the species Mallotus villosus preserved inside of a concretion, collected from Ontario, Canada. These uniquely preserved fish have beautifully preserved bone structure and are found by cracking open the hard concretions. Only the pictured half of this concretion is included.

There are two repaired cracks through the concretion.

These nodules formed within the Pleistocene-aged Leda Clay. This clay formation occurred as a result of an inland sea known as the Champlain Sea, formed from massive glaciers. The weight of these glaciers caused the Earth's crust to sink, which proceeded to be filled in by the Atlantic Ocean following the recession of the glaciers. These waters were home to a variety of marine fauna, including the Capelin fish.