When You are buying silver jewellery, you have to ask the
seller how much silver is in the piece as jewellery metal. Unlike in the case
of gold jewellery hallmarking in silver is treated with a kid glove. Though
there are legal teeth enforcing this for international trade, domestic street
jewellers shy away from the practice of hallmarking due to the cost factor.
Nevertheless, if you ask them, most jewellers or their sales assistants would
oblige by giving you the percentage of silver that went into the article. This
is what we call as purity of silver.
The purity of silver, is determined by a Metric system that
takes into account the Millesimal Fineness of the main metal used in a piece of
jewellery. Basically this denotes purity of the main metal as parts per
thousand of the mass of the alloy. Such a purity can be conveyed in three
forms. One is to express it as a percentage of the mass of alloy say 99.9%;
another way is to say it in number as 999; or in decimal form as 0.999. The
decimal representation is also supplemented with the common name in which it is
popularly known. For example 0.999 is added with the tag “fine silver”.
The fine silver is pure silver that is much malleable and
ductile shining with the lustre and brightness comparable to gold. Yet it is
too brittle and breaks and bends while on the production table. Hence, it is
necessary to add external metals as alloys to give fine silver strength and
hardness and other features necessary to make durable jewellery. There are
several combinations in which such alloys can be made. Still a common rule
applies: in order for a piece of jewellery to be sold as silver jewellery it
must contain at-least 50% silver as the main metal. In certain countries
legislation provides a legal minimum for silver in jewellery. For example in
the USA, unless it contains 925 silver it cannot be marketed as silverjewellery. Elsewhere jewellers have more elbow room. They turn out pieces with
varying percentage of silver in it. Here are few of the most commonplace ones:
1. 925 Silver: Alternatively known as ‘sterling silver” this
type contains 925 silver per thousand. By and large, sterling silver is toasted
as the standard in many countries including USA and UK. Most jewellers have
pleasure in fabricating eye-pleasing 925 jewellery articles using different
metals as alloys adding up to 75 parts per thousand. An interesting feature of
alloying is that sometimes the resultant material carries the name of the major
alloy used there in addition to silver. When silver 925 is alloyed with
germanium it is referred to as “Argentum silver”; likewise when Palladium is
the major alloy used in an article it goes as “Palladium silver”
2. 935 Silver: Used more in hand-made jewellery 935 silver
contains that amount of silver per thousand and an alloy of 65 per thousand.
This type of silver is more amenable for intricate carving and exquisite form
of gem & jewellery
3. 958 Silver: Alternatively known as “Britannica silver”
this type contains 958 silver per thousand with the remaining as alloy metals.
Notably, 958 comes out well in thin and soft pieces such as chains
4. 950 Silver: Though the silver content is restricted to
950 per thousand, this type is most popular in France and Mexico where once
upon a time this was the silver standard in coins in the respective countries
5. 900 Silver: Once the silver standard for coins in USA,
900 silver is popularly known as “coin silver” amongst the jewellers. However,
it does not restrict the name coin silver being used for an alloy containing
less than 900 per thousand. Exercise care when dealing with silver jewellery
marked as coin silver grade. It is better to see the hallmarking in addition to
the name coin silver in such piece of silver jewellery.
