Gold And Silver: The Two Precious Traditional Coinage Metals Four transition metals make up group 11 of the periodic table of elements. All, except one, are considered traditional coinage metals. Qualifying this further, only two of these three traditional coinage metals are considered precious metals. In another definition, noble metals may refer to electrically conductive elements. Here, the term "noble" serves as a modifying word, such that the electrical conductivity of materials is graded from noble to active. Using this definition for noble metals then, we will find that silver is less noble than, say, graphite (although graphite is an elemental form of carbon and, therefore, is not considered a metal). mol-1 (third) Ruthenium-palladium and ruthenium-platinum alloys are used in making electrical contacts for wear resistance. As a matter of fact, ruthenium is a very effective hardener for both palladium and platinum. When a small amount of ruthenium is added to titanium, the latter's corrosion resistance is improved significantly. These metals are not radioactive and are mostly used for industrial purposes and for jewelry. Still, precious metals have some safety issues attached to them: Rhenium: Since rhenium is used in very small amounts, its toxicity is virtually unknown. The hazardous property of rhenium halide, for example, may be attributed either to rhenium itself or to the other elements that make up the compound. Gold Standard: Definition And The Three Distinct Kinds The gold standard is defined in many different reference materials as a monetary system in which the unit of currency used is a fixed quantity or weight of gold. Under this system, all forms of money, including notes and bank deposits, were freely converted into gold at the fixed price. Electrical and electronic products (silver paints are used in making printed circuits; silver electrical contacts are used in making computer keyboards). 5. Dentistry (silver-mercury alloy is used in making dental amalgams). 6. Optics and mirrors. 7. Various industrial and commercial uses (silver is ideal for use as a catalyst in chemical reactions).