On the average (considering the consistent rise in the exchange rate of gold), the value of gold is around USD12 per gram. Here, it is clear that the currency value assigned by the government to a gold bullion coin has no meaning. Below is a list of some of the government-issued gold and silver bullion coins: 1. mol-1 (third) Palladium is used in the following: 1. Catalytic converters; 2. Jewelry and watch making; 3. Dentistry and surgical instruments; 4. Aircraft spark plugs; 5. Electrical contacts; 6. Connector platings; 7. Manuscript illumination. Since the late 1930s, palladium has been utilized as a precious metal in jewelry. It is used, customarily and legally, as a means of payment or a medium of exchange. Gram and troy weight are the units of measurement used for gold. To indicate the amount of gold present in, say, a piece of jewelry, the term "carat" is used. A necklace, for instance, that is 24 carats means that it is made of pure gold. Similar to the other precious metals in the platinum group, osmium can be found in alloys with copper or nickel. The extreme toxicity and volatility of osmium's oxide makes it nearly impossible for this element to be used in its pure state. For this reason, it is often necessary to alloy osmium with other elements for use in high-wear applications. For example, Mexico, the Philippines, and Japan pegged their respective silver units to the U.S. dollar at fifty cents. Gold Bullion Standard: In this gold standard, gold bullion is sold on demand at a fixed price. It was introduced in 1925 by the British Parliament in an act which at the same time voided the gold specie standard. One way of investing in platinum is through platinum ingots. Platinum ingots are first assayed and hallmarked before being sold on commodity markets. Another way of investing in platinum is through platinum coins. Platinum coins are internationally recognized forms of currency and have the ISO code XPT.