Generally speaking, there is no problem in woman’s wearing gold chains on her leg. However she has to hide them from non-mahram men. Leg is part of the woman’s `Awrah that should not displayed before non-mahrams. Some women do hide them but they shake their legs so to make the voice of the chains heard by men. This form of seduction is also prohibited. Allah says what means: “… And let them not stamp their feet so as to reveal what they hide of their adornment…” (An-Nur 24: 31)