Any Thoughts On My Ceres?

I have very limited knowledge of collecting especially the foreign issues, but I remember this one from years ago when I had a foreign catalog. If I remember correctly this stamp is a part of a highly desirable type of old French stamps. This one has a heavy cancel and has some envelope paper stuck to the back of it. I am sure that doesn't help whatever value it does have. I don't have a foreign catalog my library did not have in stock. I went to E-bay there were none listed like this one. Any help would be appreciated.