Gold has stood the test of time as the most popular choice for jewelry, whether bridal or fashion styles. In its purest form, 24 karat, its bright yellow, very soft, and easily scratched. Other metals, like zinc, palladium, nickel, copper, and silver,( to name a few), are added to improve its strength and polish luster, as well as to impart a variety of colors to finished pieces.
Karat gold, (18k, 14k, and 10k), are defined as purity levels, 75% and 18k are equals, for example, containing 18 parts gold, and 6 parts other metals. Fourteen karat gold would have 14 parts gold and 10 parts other metals.
Platinum is used in most of the same styles offered in gold. Many believe it to be stronger than gold, which is really a misunderstanding. It does last longer in daily wear, especially noticeable in thin petite styles, but it actually scratches, dents, and bends easier than gold. Platinum used in jewelry today is 95% pure, with palladium and iridium used in the alloy to add polish luster.
Silver is not a good choice as a setting metal for rings, etc. It works very well as chains or bracelets, but is too brittle for prong setting fine gems.