Does not fade. Due to lifestyle and personal physique, some people's sterling silver jewelry will be oxidized and blackened. You can clean it with a silver polishing cloth/toothpaste and toothbrush to restore the brightness.
Everything that goes into making the Wiccan jewelry brings its own energy into it. The metals, the gem stones, the symbols, even the colours. They all have meaning, and certain powers. You can choose your jewelry so that these materials support your goals. In this way, your jewelry can become a magick spell.