Mother of Pearl Shakers

Mother of Pearl shakers are very popular and can come in both decorated and undecorated versions. The patterns were created by trapping air creating the different patterns. In many types of Victorian glass this type of glass is quite common but in shakers and mustard jars they are quite scarce.
From left to right, the first three are differnt shakers and the right one is a mustard jar with decoration.
I believe that most of these pieces were produced by Mt Washington and Phoenix but Im sure others produced these too.