AMM270 Ammonite Fossil (South Dakota) Polyhedroids Horizontal banding

Horizontal banding

and translucent yellow calcite

Size range is approximately 2 - 3 inches in length

dark golden yellow

and white banding with mossy patterning and a dark

AMM270 Ammonite Fossil (South Dakota) Polyhedroids Horizontal bandingThis ammonite specimen comes from South Dakota in the Cretaceous period when the area was submerged by the Western Interior Seaway millions of years ago. They are typically preserved in hard concretions that must be carefully removed. This sizeable fossil shows leafy suture patterns and outer ridges in pale yellow calcite and shades of tan and brown. 4" x 3" 6oz (172g) Ammonites are prehistoric nautilus related to the modern day nautilus, squid, and