Silver may be used as an investment like other precious metals. It has been regarded as a form of money and store of value for more than 4,000 years, although it lost its role as legal tender in developed countries when the use of the silver standard came to an end in 1935. Some countries mint bullion and collector coins, however, such as the American Silver Eagle with nominal face values. In 2009, the main demand for silver was for industrial applications (40%), jewellery, bullion coins, and exchange-traded products. In 2011, the global silver reserves amounted to 530,000 tonnes.
Millions of Canadian Silver Maple Leaf coins and American Silver Eagle coins are purchased as investments each year. While these bullion coins are legal tender, they are rarely accepted by shops. However, "junk silver" coins, which were originally minted for circulation, can still be found in circulation, albeit rarely, and are common targets in the practice of coin roll hunting.
The price of silver is driven by speculation and supply and demand, like most commodities. The price of silver is notoriously volatile compared to that of gold because of the smaller market, lower market liquidity and demand fluctuations between industrial and store of value uses. At times, this can cause wide-ranging valuations in the market, creating volatility.
Silver often tracks the gold price due to store of value demands, although the ratio can vary. The crustal ratio of silver to gold is 17.5:1. The gold/silver price ratio is often analyzed by traders, investors, and buyers.
The gold/silver ratio is the oldest continuously tracked exchange rate in history. In Roman times, the price ratio was set at 12 (or 12.5) to 1. In 1792, the gold/silver price ratio was fixed by law in the United States at 15:1, which meant that one troy ounce of gold was worth 15 troy ounces of silver; a ratio of 15.5:1 was enacted in France in 1803. The average gold/silver price ratio during the 20th century, however, was 47:1.