F. Weber CO. Artist's sandpaper pad

I found this little pad of artist’s sandpaper among a couple other items in my father’s old drawing and drafting supplies. He is not alive for me to ask but these items could have also been his grandfathers. I’m not sure how old this item is.
 

F. Weber CO. is an American manufacturer and supplier of artists' materials. Established in 1853 in Philadelphia, Pennsylvania, the F. Weber Company, Inc. is the oldest and one of the largest manufacturers of art materials in the United States. F. Weber is a successor company, established in 1853. This company won many gold medals for its fin quality products in the World Fair. 

The founder’s sons were talented artists and chemists, leading to the numerous innovations in their time.  A majority of these innovations decreased the toxicity in many art supplies.

The company was later bought by an industry in New York, and in honor of the Weber family, the name was kept on the products.