Harpoceras Ammonite | Germany Tumbled Stones The use of flint to

The use of flint to make stone tools dates back millions of years

9 million years ago

These organisms first emerged in the fossil record during the Darriwilian stage of the Middle Ordovician period

The extinction of the ammonites

Harpoceras Ammonite | Germany Tumbled Stones The use of flint toHarpoceras sp. Early Jurassic (180 MYO) Posidonia Shale Holzmaden, Germany Ammonite approx. size: 8. 5" x 7" Plate approx. size: 13. 5" x 10. 25" This Harpoceras ammonite from the Posidonia Shale in Holzmaden, Germany has been compressed on black slate and is partially pyritized. Ammonoids are a group of extinct marine mollusk animals in the subclass Ammonoidea of the class Cephalopoda. These mollusks, commonly referred to as ammonites, are more