...Bullion & Money
Silver has been used historically and cross-culturally as money. In
fact, the words "silver" and "money" are the same
in many languages. Silver is one of the so-called "coinage"
or "noble" metals because it is a relatively inert and corrosion
resistant metal that is used for minting coins. Being more geologically
abundant and cheaper than gold, silver can be used in the smaller denominations
of coins that are typically use in daily transactions.
In the United States, as recently as 1964, silver was used in U.S. dimes
and quarters. In 1969, the United States Mint issued the last 40% silver
U.S half-dollars.
Precious Metals & Money
Over the last few hundred years there has been a gradual, international
drift away from using precious metals in national coinage or as the
backing for value of national currencies.
When a currency is backed by a precious metal, currency issuers guarantee
to redeem notes of that currency for a set amount of that precious metal
and so the price of both the currency and metal are "fixed"
to each other. When that link is broken, the currency and price of the
metal are said to be "allowed to float freely". At that point
the metal is priced by markets. Simultaneously, the currency is said
to becoming a "fiat" currency, which holds value due to the
authoritative mandate of the issuer.
The decision to continue to use fiat
money as national currencies is the basis of a great deal of political
and economic debate and often tied to discussions of inflation.
In the United States, the U.S. dollar was initially backed by both gold
and silver. In 1900 the dollar became backed by just gold though silver
was used in coinage, so the price of gold and silver continued to be
stable and linked, and in 1975 the gold standard was removed and the
dollar became a fiat currency.
Silver Markets & Price
In the beginning of the 21st century, even though silver is not materially
used as coinage or as the conceptual backing for most currencies, it
is still used, in part, as a store of wealth in the form of bullion.
Market action at large commodity exchanges in Chicago, New York, Dubai,
Sydney and Tokyo regularly update the price of silver and that information
is communicated around the planet via the Internet.
Here are a couple examples of online charts showing recent silver prices:

Silver is traded on the large exchanges in the form of 100oz bullion
bars. Individual investors typically purchase smaller 10oz bullion bars
and 1oz coins. The one-ounce, .999 pure silver coin is the most typical
form of purchase for the small investor. The silver
ticket is minted in a one-ounce ingot so to be comparable to the
typical investment size.
Coins
Both national and private mints mint bullion into investment forms.
The American
Silver Eagle and the Canadian
Silver Maple Leaf are two examples of one-ounce nationally minted
coins that are typically collected.
American Silver Eagle
Canadian Maple Leaf
These coins sell for a small markup over the market price of silver.
Most of the bullion coins now minted by national mints have a face value
and are officially money but are not used as such because the value
of the metal is worth more than the face value. The Silver Eagle has
a face value of one U.S. dollar and the Silver Maple Leaf has the face
value of five Canadian dollars.
Some silver owners feel that the designation, of these official bullion
coins as money, protects the investor from a rapid fall in market prices
for the metal. So if silver were to become worth less than a dollar/ounce
an American Eagle coin could at least be used as a dollar coin and so
hedging the investment somewhat.
Some silver owners also feel the designation, as money, will protect
them in the case of government confiscation. In 1933 the U.S. government
confiscated all privately held gold with the exception of some coins
deemed as collectables. The concern is that, since silver is a valuable
industrial and financial commodity, in a time of crisis the government
may try to confiscate silver. Others
argue there is just too much of silver out there to practically collect.
This issue has been addressed
by the Mint though some people are still concerned.
Another concern is by designating silver, as money, it gives the government
more control over how the metal. A example of this is the control of
base metals used in coins in the 2006
interim rule that generally prohibits the exportation, melting, or treatment
of United States one-cent coins (pennies) and 5-cent coins (nickels).
Private Mints produce one ounce silver coins that are referred to as
"generic rounds" or just "rounds". These coins do
not have a face value and are often a bit smaller in radius and thicker
that the national bullion coins so not to be seen as attempted counterfeits.
They sell for a slightly smaller mark up over the price of silver. These
coins are often produced with commemorative designs and can be found
stamped with faces of war and sports heroes as well as generic nationalistic
iconography like eagles and neo-classical decorations.
Silver in Alternative Currencies
There are examples of private, alternative currencies using silver coins.
The Liberty
Dollar and is a popular example.
Liberty Dollar
In 2006 the U.S. Mint issued a press
release stating that prosecutors at the Justice Department had determined
that using Liberty Dollars as circulating money is a federal crime.
Another contemporary twist to alternative currencies has been the introduction
of electronic currencies backed by precious metals (aka: e-bullion,
goldmoney, e-gold). Typically the e-currency is denominated by weight
such as grams or ounces and can be used as a way of investing in precious
metal as well as money for making purchases. Examples include the eLiberty
Dollar, the ePhoenix
Dollar, and e-silver.
Silver investors also invest in collectable "numismatic" coins
that include former currency coinage. These coins are valued more for
their rarity as collectables rather than their bullion content and typically
sell well above their bullion value.
Some people accumulate silver in small denomination silver coins in
case of economic and social catastrophe, with the idea that silver will
again become a currency if governments are unable to maintain the credibility
of their fiat currencies.