A fascinating video of Dominique Sennelier talking about the Sennelier colours and products in one of the Sennelier shops in Paris.
Dominique is the grandson of Gustave Sennelier who started his art supply store in 1887 close to the the most famous art school in Paris, Ecole des Beaux-Arts. At the beginning he only sold colours made by other manufacturers before deciding that he needed to start making his own.
Various media are discussed in the video. Mr Sennelier mentions that the soft pastel range has "only 579 colours". The oil stick they created was originally made for Picasso. The formulation for egg tempera is very old as this was a very traditional type of paint and was used before oil painting.
See also my post Making a Mark Reviews: Art shop review: Magasin Sennelier, Paris.