Help Identify French Test Stamps

Hi all,

Does someone know something about these test stamps?

They were together with a collection of French Chambon test stamps but they are not listed in any test stamps catalogue that I know of...

The image (a saddled rhinoceros) is a reproduction of a famous Chinese bronze sculpture from the Western Han dynasty... so maybe a test stamp for China...? (even though it was during the 1960s?)

Any information or thoughts would be much appreciated!
Many thanks in advance.

Welcome to Stamp Community Forum, Teststamp257!

Is there a way (reference) that you know that the country of origin is France?

Thanks bookbndrbob!

It was part of a big lot of French test stamps that my grand-father gathered when he was working for the Chambon company (in the 60s etc).
However, being a collector himself he might have obtained some test stamps from somewhere else so I cannot be absolutely certain that these rhinoceros come from the factory where they were doing the tests on the machines... but the chances are high let's say.

One odd thing is that the paper is quite thick and rigid, not like typical stamp papers...