Gold dissolves in mercury, forming amalgam alloys, but does not react with it. Gold is insoluble in nitric acid, which will dissolve silver and base metals, and this is the basis of the gold refining technique known as inquartation and parting. Nitric acid used to confirm the presence of gold in items, and this is the origin of the colloquial term acid test, referring to a gold standard test for genuine value.

American Gold Eagle

The American Gold Eagle is an official gold bullion coin of the United States. Over the years, the gold Eagle from the US mint have become the USA’s most popular bullion coin, and our biggest gold coin seller by far. Each 1-ounce gold Eagle contains a full 31.1 grams of pure gold, with an additional alloy of silver and copper, bringing the total weight up to about 33.9 grams. Coins Offered in 1/10 oz, 1/4 oz, 1/2 oz, and 1 oz denominations. U.S. government guarantees them to contain the stated amount of actual gold weight in troy ounces. By law, the gold must come from sources in America, with an additional alloy of silver and copper to produce a more wear-resistant coin of .9167. It authorized by the United States Congress and backed by the United States Mint for weight and content. The market value of the coins is generally about equal to the market value of their gold content, not their face value. Gold Eagles from the U.S. Mint are the most popular gold bullion coin in this country, and now make up over 80% of the U.S. physical gold bullion market. This bullion product has been a tremendous success for the U.S. Mint.; their actual selling prices vary daily based on the current spot price of gold. The face values are proportional to the weights. The one-ounce gold Eagle has a $50 nominal face value, is 91.67% fine gold, and weighs 1.0909 troy ounces. The most popular size bullion coin issued 20 coins per Treasury tube. The half-ounce gold Eagle has a $25 nominal face value, is 91.67% fine gold, and weighs .5455 troy ounce. The least popular size bullion coin, and often the lowest mintage, it is issued 40 coins per Treasury tube. The quarter-ounce gold Eagle has a $10 nominal face value, is 91.67% fine gold, and weighs .2727 troy ounce. About the size of a nickel, it is popular in jewelry. It issued 40 coins per Treasury tube. The tenth-ounce gold Eagle is a $5 face value coin, 91.67% fine gold (22 karat), and weighs .1091 troy ounce. Smaller than a dime, it is a popular small gift item. It issued 50 coins to a Treasury tube. The obverse design features a rendition of Augustus Saint-Gaudens' full-length figure of Lady Liberty with flowing hair, holding a torch in her right hand and an olive branch in her left, with the Capitol building in the left background. The reverse design, by sculptor Miley Busiek, features a male eagle carrying an olive branch flying above a nest containing a female eagle and her hatchlings.