Chapter 84:18-19
Laws of Carrying: Clothing & Jewelry
18.Bald men who wear a toupe' may wear it in the public domain on Shabbos
(provided they are prepared before Shabbos), because they are considered an
ornament ("tachshit").
19. A person should consult a Rabbinic authority as to whether he is
permitted to go out wearing an amulet ("kamia") on Shabbos or not, because
there are different rulings depending on the nature of the amulet (1).
A woman who wears a stone called "sternschus" as a charm against
miscarriage, may go out wearing it on Shabbos.
FOOTNOTES:
(1) Mishna Berura 308:129