Hastings' Dictionary of the Bible (1898) & Schaff's Bible Dictionary
AM'ULET. The superstitious character of the Oriental nations has in all periods led them to fear the attacks of imaginary foes, and so, in order to protect themselves, they wear charms of one sort and another. These amulets are indirectly and directly referred to in the Bible; e. g. when in the form of Egyptian Amulets. ) 1. Gold. 2. Ring with the word "health" inserted. 3. Scarabaeus. 4. Cornelian serpent's head. 5. Porcelain eyes. 6. Gold pendant, inlaid. ear-rings. Gen 35:4; Jud 8:24; Hos 2:13.
But more commonly they were worn suspended from a necklace as a gem with an inscription or figure of a god upon it. Charms consisted likewise of words written upon papyrus or parchment rolled up tightly and sewed in linen; perhaps these are meant by the "tablets" of Isa 3:20. Phylacteries, some suppose, derived their sanction from the danger of idolatrous practices to which this custom gave rise.