Mariner chain necklaces are one of the toughest chains available. It has the same strength as the curb and cable chain. The only difference is that it is silver instead of gold. Mariner chain is made up of a large circle that is divided into two sections with a horizontal link in between. These links are then connected to each other using a square knot or a half hitch. The end result is a long loop through which a metal badge, also called a ferrule, can be inserted. This keeps the necklace from breaking if it is pulled hard enough to stretch out the chain. The term "mariner's chain" comes from the fact that these chains were originally used by sailors to protect their necks from being bitten by sharks. They were made out of the same materials as modern-day mariner's chains but were not as heavy because they had to be flexible. These chains are very popular among men who like to wear jewelry that displays their taste in style. They make excellent gifts for guys who love sports cars or old school motorcycles.