Yes it is earlier than 1940, the American 'Fantasy Crystal' catalogue dates 1919-1930 and the French version has 1926 on it, but there are some pieces in it that date back to 1920, that got included in it. I've got several examples on my Pinterest page ... sorry, I'm not advertising myself but it's all there ... just search for Val St Lambert and you should come across it. If I need to translate, just let me know....
Back to that site, for instance the mentioned 1926 Fantasy Crystal catalogue, which is dated 1908 and incorrect on this site .... I only get three pages on my screen and nothing opens or happens when I click on anything, so I must be doing something wrong?