Bohemian Garnet Stone Cluster Setting Ring Size 6

Bohemian Garnet Stone Cluster Setting Ring Size 6 with Sizer on it This was my grandmothers ring. It has a ring sizer on it which has worn on the sides of the ring. See pictures I don't see any markings but the ring sizer is in the way and I am not sure how to remove it. All the stones are intact and secure on the ring. Non smoke home