Antique Blonde Turtle Shell.
This superb example is the top of the carapace
The colour is a tawny blonde. The scientific name is Podocnemis expansa.
These shells come from South American river Turtles & in the 19th century ships purchased the animals for food/ meat to have on board.
The shells were then hand polished by the sailors on the homeward voyage to be given as presents or sold for extra money