These are real fragments of fossilized diplodocus dinosaur bones!
They are the leftover remains of a diplodocus skeleton, excavated in the Morrison Formation of Wyoming, USA. These Jurassic fossils were hand-collected by Ben Lovatt, the founder of the Prehistoria Museum, in the spring dig season of 2022.
They come in ~3.25" Riker frames and can be shipped worldwide.
Diplodocus is one of the longest dinosaurs ever discovered! This species is famous for having a double row of bones along the underside of its tail to provide extra support - such a distinct feature that it lead to it's name (“diplos” is Greek for double and “dokos” means beam).