This is the original stunt sword used by Tim Roth (as the ape Thade) in Tim Burton’s 2001 film Planet of the Apes.
It was designed by Academy Award winner Colleen Atwood and custom made for use on set.
Thade’s sword is made out of hard rubber over a metal frame.
The sellers says:
It comes with a signed certificate of authenticity from Studio-Props. We purchased this item directly from 20th Century Fox and have placed a copy of our receipt from Fox on the C.O.A. to prove it.
The sword is available for sale (for $2,250) and more images of it can be viewed on Ebay at the link below: