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Sterling silver has been used since humans discovered the versatility of the
metal.
There have been
practical uses from flatware to armor, in addition to creating beautiful
sterling silver
jewelry in the ancient Byzantine, Phoenician, and Egyptian empires.
Today, Mexico and Peru
are the highest producing sterling silver mines in the world. Sterling
Silver jewelry is popular among younger people because of the
affordability and beauty of the metal. Sterling Silver Jewelry charms, rings,
and chains are a great alternative to white gold or platinum. It is the most
reflective metal, so can be polished into a higher sheen than other white
metals. Silver is also quite affordable and looks beautiful as silver charms,
chains, necklaces, earrings, rings, bracelets, bangles and watches.
The only problem with Sterling silver jewelry is its tendency to scratch and
tarnish over time. Proper care is required to keep it looking beautiful and shiney. Fine silver, which is at its natural state, is
999/1000 pure. That kind of purity makes it too soft for molding into
everyday products. In order for silver to be hard enough and suitable for
arts and crafts, alloying with other metallic components is a must.
Sterling silver is a mixture of 92.5% pure fine silver and other metal
alloys. It is the most popular concentration found in silvery items, and a
marking of "925" can be visibly noted engraved onto either the
backside or the inside of each piece. It is the most ideal percentage for
having enough durability without loosing much of the natural bright sheen.
Silver plating is when a base metal is covered with a layer of pure silver.
This form of production is a popular alternative for more affordable prices.
However, it will be necessary to coat the jewelry item with a layer of silver
every once in a while to keep the base metal from showing through over time
and wear. Vermeil is sterling silver jewelry electroplated with at least 100
millionths of an inch of karat gold, giving it a nice and sophisticated
appearance. German or Nickel silver is a silvery-white alloy consisting of
copper, zinc and nickel. But since many people have allergic reactions to
nickel, this form is not as popular in products worn against the skin. When
shopping in the market for silver pieces, look for the mark 925, .925 or
Sterling Silver. Those marks mean that the item is 92.5 % pure rather than
being plated or German/Nickel silver, which is basically just an imitation of
the metal. 925 is the best form due to their durability and high sheen.
Be sure to store your sterling silver jewelry in a cool, dry place
individually in pouches to keep them from environmental harm. But don't sweat
it if your item becomes tarnished, chances are it'll happen no matter how
careful you are. Just use a polish solution or a polishing cloth to clean the
piece. Sterling silver is the most reflective out of all precious metals, so
keep it beautiful and it'll capture your heart for a lifetime.
Dictionary:
Sterling silver: n.
1) An alloy of 92.5 percent silver with copper or another metal.
2) Objects made of this alloy.
More information on sterling silver jewelry and metal:
Sterling silver is at least 92.5% silver and up to 7.5% other metals, usually
copper, and is stamped with either the word "Sterling" or
".925" or the Lion Passant mark. Fine silver (99.99% pure) is
generally too soft for producing large functional objects. Compare with CuAg, which is a brand for a similar alloy, (72% silver,
28% copper) known for its thermal conductivity.
Origin of the term
Sterling silver:
The term "Sterling Silver", in reference to the .925 grade of
silver, emerged in England
by the 13th century.
The terms "sterling" and "pound sterling", seem to have
acquired their meaning over a period of time, and from several convergent
sources. The first mention is that of "sterilensis"
in 1078, and by the thirteenth century (by the 1200's) the term sterling had
appeared.
"Easterling" Theory:
It seems quite possible that Sterling Silver may have been known first as
"Easterling Silver". The term "Easterling Silver" was used to refer to the grade of
silver that had originally been used as the local currency in an area of Germany,
known as "The Easterling".
This "Easterling" consisted of five towns
in the eastern part of Germany
which banded together in the 12th century under the name of the Hanseatic League. The Hanseatic League proceeded to engage in considerable
commerce with England.
In payment for English cattle and grain, the League used their local
currency. This currency was in the form of 92.5% silver coins. England
soon learned that these coins, which they referred to as "the coins of
the Easterlings", were of a reliably high
quality and hardness.
King Henry II set about to adopt the alloy as the standard for English
currency. He imported metal refiners from the Easterling
and put them to work making silver coins for England. The silver these refiners
produced came into usage as currency by 1158 in the form of what
are now known as "Tealby Pennies", and
was eventually adopted as a standard alloy throughout England. The original term of
"Easterling Silver" was later abbreviated
to "Sterling Silver".
Though the coin weights and silver purity changed considerably in the
intervening time (reaching a low point before the reign of Elizabeth I, who
reinstated Sterling Silver coinage for the first time since the early 14th
century), the pound sterling was used as currency in England from the 12th
century until the middle of the 20th century. Specifically this was in the
silver coins of the British Empire -- Britain, British colonies and
some former British colonies. This sterling coin silver is not to be confused
with the Coin silver standard.
Sterling silver, while no longer used in circulating currency anywhere in the
world, is still used for flatware, jewellery and
plate, and is a grade of silver respected for both relatively high purity and
sufficient hardness to form durable objects in daily use.
Mint Mark Theory:
Another credible theory is that, since mint marks on Sterling Silver pennies
have included a star and a starling, this may be the origin of the word -- as
a simple corruption of, for example, "starling silver" with common
reference to the circulating coin.
Other Silver Standards:
Fine Silver is 99.9% silver or better. This grade of silver is used to make
bullion bars for international commodities trading. In the modern world Fine
Silver is understood to be too soft for general use.
Britannia silver is purer than sterling, at least 95.84% silver and up to
4.16% copper. Its marks were Britannia and a Britannia lion's head in
profile.
The Britannia standard was a standard of plate introduced between 1697 and
1720 to try to help prevent British sterling silver coins from being melted
to make plate. Unfortunately the plate made from this grade of silver was too
soft to use for the then current style in plate, so a simpler plate styling
had to be developed.
Mexican silver is also purer than sterling, usually 95% Silver and 5% Copper.
Mexico
is the only country currently using silver in its circulating coinage, but
these coins are not minted from 95% "Mexican" Silver.
Coin Silver is 90% silver and 10% copper as dictated by United States FTC
guidelines.
Coin Silver is lower grade than sterling. The Coin Silver standard was
established in the US
in the 1820s. This grade of silver was used in the silver coinage of the US as well as other countries that used silver
currency minted in the US,
such as Panama and the Philippines.
Corrosion:
As the purity of the silver increases, the problem of corrosion or tarnishing
lessens.
Chemically, silver is not very active — it does not react with oxygen or
water at ordinary temperatures, so does not easily form a silver oxide.
However, the other metal in the alloy, usually copper, may react with oxygen
in the air.
Silver tarnish, however, is the formation of black silver sulfide on the
surface of the metal. This tarnish is caused by sulfur and sulfides which
attack the surface of the silver. Because of this, the rate of discolouration of silver by tarnish is worse with higher
levels of these airborne pollutants.
Eggs, which contain a considerable quantity of sulfur as a constituent of
protein, tarnish silver extremely quickly. Small amounts of sulfide occur in
the atmosphere naturally, but another major man-made source is hydrogen
sulfide (H2S), which is added to natural gas used domestically. Hence a gas
flame can also tarnish silver.
The black silver sulfide (Ag2S) is among the most insoluble salts in aqueous
solution, a property that is exploited for separating silver ions from other
positive ions.
Removing tarnish:
A very popular technique for removing tarnish involves the creation of an
electrochemical cell. If the other metal is anodic relative to silver, then
the silver in the sulfide will revert to metallic silver. The metal at the
anode will be oxidized. The sulfide ions can travel to the anode via the
electrolyte (solution). Metals that will work are iron, zinc, aluminium and magnesium. Aluminium
foil is cheap.
A typical procedure is to line a pyrex glass dish
with alumimium foil so the bright side of the foil
will contact the solution. Add one litre of water,
and heat until near boiling.
Add one tablespoon of sodium chloride and one tablespoon of sodium
bicarbonate, and gently stir to dissolve. Ensure that the silverware has been
washed in warm dishwashing detergents, and well rinsed in warm water to
remove dirt and grease.
Carefully add the silverware to the dish, ensuring that each item is in
contact with the aluminium foil, and boil until the
tarnish has disapppeared, turning the silverware if
necessary. The continuous boiling is required so that the aluminium
oxide continually exposes the unreacted aluminium surface beneath,
otherwise the reaction will not occur. The aluminium
will gradually be converted to aluminium oxide. The
hydrogen that is generated in the reaction will combine with the sulfide ions
to produce some hydrogen sulfide gas (rotten egg gas).
It should be noted that the process is not converting the silver back to the
original hard, lustrous surface, but into a soft, white powder that can be
removed easily by rubbing with a little bicarbonate of soda paste. The silver
powder will be easier to remove than the tarnish would have been.
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