Edmontosauras vertebra (tail). Edmontosaurus was 40 feet long plant eater.
I purchased this one at Dinosaur World, Central Park Mall, in San Antonio, Texas, about $15 taxi drive from its downtown.
I like its color and surface reality.

Fossil Dinosaur Bone (65x65x60 mm)
Fossil Description: Edmontosaurus Vertebra
Taxon: Montana, USA
Provenance: Cretaceous
Formation: 136 to 65 Million Years Old