Italian Cameos that my grandfather brought back from italy during World War II

There are quite a few cameos here that my grandfather brought back with him from italy during World War II. i have separated them into 2 groups. one that i believe to be made from shell and the second group im not sure of the material.in the shell group there are two that are facing to the left which leads me to believe they were made by a left handed person. there is one that is facing forward in the other group, not sure what that means. if you could tell me the value of these that would be great. i would like to sell them individually or as a group....thank you very much...Todd