There are certain rules for wearing jewelry with Allah engraved written on it. If a person goes to the toilet with a ring on which the name of Allah or the Prophet is written, he or she should hide his ring. If the ring is on the left hand, he or she should remove it when he cleanses himself. (Ibn Abidin, V, 317). Accordingly, a person who has a necklace on which the name of Allah is written can go to the toilet by covering the name or turning the back of the necklace. There is no difference between wearing it and a himala (a piece of paper containing verses from the Quran or prayers and wrapped usually in the form of a triangle). The himala includes prayers and verses. Click here to find out more.