Lammer Beads

Does any one know the meaning of "Lammer beads?" They are almost always made of amber, and are considered as a charm to keep away evil of every kind; their touch is believed to cure many diseases, and they are still worn by many old people in Scotland round the neck. The name cannot have anything to do with "Lammermuir," as, although they are well known among the old people of Lammermuir, yet they are equally so all over Scotland.