Precious Metals
It is the precious metals that provide the raw materials for the creation of items of jewellery.
The three most popular precious-metals used in jewellery are gold, silver & platinum. In recent years, palladium has also increased in popularity due to its extraordinary properties and that it is classified as a “white-metal” – white metals of which have been very fashionable for many years now.
All the precious metals have their own characteristics that make them ideal for use in jewellery. However, all of the precious metals share the following attributes:
- Allure
- Malleability
- Durability
- Rarity
All of the precious metals are usually alloyed for use in jewellery. For example, pure gold – although the term itself is enchanting – is limited for use in jewellery. For hundreds of years artisans have mixed gold with other metals resulting in a harder material which is more impervious to scratching. Another purpose of alloying gold is so that manufacturers are able to alter the colour – rose gold, white gold and even green gold have been popular for many years. Gold is available even in blue and purple!
Gold
The rich natural yellow colour of gold inspired the ancients to associate it with the energy and health of sunlight.
Gold (Latin name Aurum, chemical symbol Au) is a highly popular precious metal used in jewellery. Gold is highly lustrous, hefty (dense), soft, and the most ductile (the ability to be formed into a variety of shapes) of the precious-metals.
The gold alloys, with varying degrees of gold-fineness accepted and sold in the UK are as follows:
- 9ct gold (.375)
- 14ct gold (.585)
- 18ct gold (.750)
- 22ct gold (.916)
The numbers denoted in parenthesis are “parts per one-thousand” of gold in relation to the other alloyed metals. E.g. 18ct gold has 750 parts in every 1000 total parts – the other 250 parts will be the other alloying metals. These alloying metals (depending on the purity and colour of the gold) can be a combination of copper, zinc, silver and palladium.
Another way of conveying this would be to consider that 18ct gold is 75% pure – the other 25% consist of the alloying metals.
All the different finenesses – with the exception of 22ct gold – can be altered in colour. 22ct gold is too pure – the smaller percentage of the alloying metals limits the ability to change the appearance although 22ct gold is often plated with rhodium.
Silver
Silver is the most lustrous of the precious metals. Pure silver reflects more than 90% of light. The standard “alloyed” silver widely recognised in the UK and elsewhere around the world is “sterling” silver (925) – 925 parts of silver per one-thousand total, or 92.5% pure.
Silver is more abundant than gold which is reflected in the price. Silver is often a by-product when other metals such as copper, lead, tin and gold are being mined.
The UK presently has four legal finesses for silver: 800, 925 (sterling silver), 958 (Britannia silver) and 999 all of which are represented by an assay office hallmark.
Platinum
Platinum is the strongest and heftiest of the precious-metals. Platinum, like gold, is categorised as a “noble” metal – i.e. it resists corrosion and it does not tarnish or discolour.
Platinum is a popular metal when used as a setting for gemstones – especially diamonds because of platinum’s hardness and reflective attributes.
Palladium
Palladium, also from the platinum family of metals, is the most recent metal to receive a British hallmark. It is generally sold at a purity of 95% (950).
Palladium has long been used for settings for gemstones but more recently palladium has found popularity when used for wedding rings because of its properties. Palladium is harder than platinum but lighter (comparable to 14ct gold alloy), it is a naturally white-metal and is hypoallergenic.
