My wifes grandparents gave her a small quill pen that looks like it is carved out of ivory.It unscrews and the steel quill pen is on one half and the other has a crystal about the size of a matchhead that when you look through it has 6 drawings.King,s road,the pavillion,the aquarium,west pier,chain pier and the electric railway.At the top of these small drawings it says “souvenir of Brighton”.Does anybody have an idea of when this might have been made? Thanks for your time.