Many people enjoy these commemorative coins because they have both a collectible value and a precious metal value. Gold coins are also issued as "commemorative" items. However, gold coins issued in specific weights are popular ways for people to purchase and own small amounts of gold for investment. Today gold coins are no longer in wide use for financial transactions. Gold coins were issued in two types of units: (1) some were denominated in units of currency, such as dollars while, (2) others were issued in standard weights, such as ounces or grams. Gold coins were commonly used in transactions up through the early 1900s, when paper currency became a more common form of exchange. The first gold coins were minted under the order of King Croesus of Lydia (a region of present-day Turkey) in about 560 BC. The vaults contain a huge trove of over 400,000 gold bars, worth approximately 252.4 billion dollars. Video: BBC's Frank Gardner visits the Bank of England to get a rare look inside their gold vaults. Today many governments, individuals, and institutions hold investments of gold in the convenient form of bullion. The gold used as a financial backing for currency was most often held in the form of gold bars, also known as "gold bullion." The use of gold bars kept manufacturing costs to a minimum and allowed convenient handling and storage. The gold standard was once used by many nations, but it eventually became too cumbersome and is no longer used by any nation. Under this gold standard, any person could present paper currency to the government and demand in exchange an equal value of gold. The United States once used a "gold standard" and maintained a stockpile of gold to back every paper dollar in circulation. Some early printings of paper money were backed by gold held in safekeeping for every unit of money that was placed in circulation. Gold works well for this purpose because it has a high value, is durable, is portable, and is easily divisible. The rarity, usefulness, and desirability of gold make it a substance of long-term value. The first known use of gold in transactions dates back over 6000 years.Įarly transactions were done using pieces of gold or pieces of silver. Add more copper, and the alloy begins to look like copper.īecause gold is highly valued and in very limited supply, it has long been used as a medium of exchange or money. As the amount of copper reaches 50%, the alloy begins to display a reddish color. Notice that the bottom side of the triangle is for different weight percentages of copper. The accompanying ternary (triangular) diagram illustrates how alloys with different percentages of gold, copper, and silver will yield different colors of gold. Other alloys yield green, peach, and even black-colored metals. White gold is an alloy of 75% gold, 4% silver, 4% copper and 17% palladium. Adding more copper shifts the color to a pinkish color, and even more copper produces a reddish gold. An alloy of 75% gold, 16% silver and 9% copper yields yellow gold. Colors of Gold AlloysĪlloying gold with other metals changes the color of the finished products (see illustration). Image by Metallos, used here under a GNU Free Documentation License. In general, high-karat jewelry is softer and more resistant to tarnish, while low-karat jewelry is stronger and less resistant to tarnish - especially when in contact with perspiration.Ĭolors of gold-silver-copper alloys: Different metal colors that can be produced by alloying different amounts of gold, silver, and copper. An alloy that contains 75% gold by weight is 18 karat (18/24 = 75%) and marked "18K". Pure gold is known as 24 karat gold and is almost always marked with "24K".Īn alloy that is 50% gold by weight is known as 12 karat gold (12/24ths) and is marked with "12K". A standard of trade known as "karatage" was developed to designate the gold content of these alloys. The alloys of gold have a lower value per unit of weight than pure gold. Since then most gold used to make jewelry is an alloy of gold with one or more other metals. Craftsmen learned that alloying gold with other metals such as copper, silver, and platinum would increase its durability. Pure gold is too soft to stand up to the repeated stresses applied to many jewelry items. Gold rings: Gold rings of different colors. Gold is a memorable metal that has found a place in the human mind. When you pick up an item made of gold, it feels distinctly "heavy" - and you sense that the object is important. Gold conducts electricity, does not tarnish, is very easy to work, can be drawn into wire, can be hammered into thin sheets, alloys with many other metals, can be melted and cast into highly detailed shapes, and has a wonderful color and a brilliant metallic luster. Its usefulness is derived from a diversity of special properties. Of all the minerals mined from the Earth, none is more useful than gold.
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