White gold is an alloy of gold and other white metals such as silver, palladium, or nickel. The natural colour of white gold is light grey and slightly yellow, so jewellery made of white gold is typically coated in highly reflective rhodium (sometimes coated in platinum and palladium), adding a more brilliant shine. Palladium and silver alloys are of higher quality than nickel and are sometimes not coated with rhodium. The purpose of plating is to add lustre to greyer jewellery, as well as to prevent oxidation of some of the metals found in the alloys. White gold is not platinum, but is used as a less expensive alternative, usually costing one-third as much as platinum. It is interesting to note that white gold for jewellery is originally developed in the 1920's as a substitute for platinum. Nowadays, they are a jewellery metal in their own right and currently very fashionable and desirable, particularly among the younger age groups. Additions of any white metal to gold will tend

to bleach it's colour, in practice, nickel and palladium (and platinum) are strong 'bleachers' of gold, silver and zinc are moderate bleachers and all others are moderate to weak in effect. There are two basic classes of white gold - the Nickel whites and the Palladium whites. The nickel-whites tend to have a colder white colour, whereas the palladium whites have a warmer colour. Good nickel whites tend to be hard and difficult to process. Good palladium whites tend to be soft, easy to process (but lost wax casting is more difficult) and are much more expensive, because of the price of palladium. Consequently, many commercial white alloys are thrifted in nickel or palladium and contain some copper; hence, colour is compromised. At the 8-10 carat (33.3 - 41.6% gold) level, gold-silver alloys are quite white, ductile although soft and are not best used for jewellery purposes. White gold is available up to 21 carat.

White gold jewellery wearers can be disappointed to discover that their jewellery has gone off-white, even a yellow-brown tint, as the rhodium plating wears through. If the

rhodium plating does wear through, the jewellery can be easily re-plated. Some people (about 12.5%) are sensitive or allergic to white gold. This occurs

because of reaction to nickel found in some white gold alloys. Reactions are mild and only involve skin rashes.

ADVANTAGES OF WHITE GOLD JEWELLERY: • LUXURIOUS WHITE PRECIOUS METAL IS NOT AS

EXPENSIVE AS PLATINUM • STERLING SILVER ALTERNATIVE WILL TARNISH

• HIGH FASHION LOOK PERFECT FOR CASUAL OR FORMAL WEAR

• BLENDS BEAUTIFULLY WITH DIAMOND SET JEWELLERY

The winning yellow and white gold combination:

COMPLETELY FASHION FORWARD AND SUITABLE FOR

ANY JEWELLERY WARDROBE HAPPENS WHEN DESIGNERS BLEND YELLOW AND WHITE

GOLD IN THE SAME JEWELLERY ARTICLE.

HOWEVER, THERE IS A

CAUTIONARY TALE HERE.

SOME JEWELLERY REPRESENTED AS “YELLOW

AND WHITE GOLD” MAY ACTUALLY BE ONLY RHODIUM

PLATING OVER CERTAIN YELLOW GOLD PORTIONS. AT

BIRKS & MAYORS, WE ONLY MARKET TRUE WHITE GOLD,

WITH THE PROPER ALLOYS THROUGHOUT—EVEN

THOUGH THE WHITE GOLD HAS A RHODIUM PLATING.

THE TOP TWO EXAMPLES PICTURE SEPARATELY MADE LINKS OF TRUE YELLOW AND

WHITE GOLD ALLOYS.

THE BOTTOM EXAMPLE IS TYPICAL MASS MARKET

ITALIAN ‘STAMPATO’ WITH RHODIUM PLATING OVER YELLOW GOLD LINKS TO SIMULATE YELLOW AND

WHITE GOLD MANUFACTURE. THIS RHODIUM PLATING WILL

CERTAINLY WEAR OFF AND LOSE THE APPEARANCE OF YELLOW AND WHITE GOLD.

PERMANENT PLATINUM Platinum is something of a late comer to the jewellery world. The naturally occurring platinum alloys were named by the Spaniards as "platina," or little silver, when it was encountered in Colombia. They regarded platinum as an unwanted impurity in the silver they were mining and often discarded it, since despite all their best efforts—it could not be melted. The best known ancient occurrence of platinum use as adornment was on the ceremonial casket of an Egyptian High Priestess and in some jewellery articles of Inca and South American Indian civilizations. This precious metal defined manufacture on a large scale, due to its much greater rarity than gold and its very high melting point (3190 F). Antique jewellery historians have catalogued very few platinum pieces in the 19th Century, although ‘Tiffanys’ of New York was the first to display platinum jewellery at the World’s Fair in the late 1870s. Platinum jewellery was then something of an exotic oddity. Louis B, Cartier of the famous Cartier jewellery dynasty, pioneered the use of platinum by aiding in the development of a super hot torch for jewellery use. The Edwardian era (1900-1914) is most famous for its platinum jewellery which was fabricated into styles simulating lacelike airy patterns.

This early platinum jewellery was the perfect complement to the light and lacy fashions of the time, and although the jewellery appeared to be delicate – it was incredibly durable. PLATINUM PURITY Platinum is the only precious metal which is always sold nearly pure in jewellery. Platinum is alloyed with 5% ruthenium or osmium and 95% platinum or 10% iridium and 90% platinum. All are platinum group metals. These mixes harden the platinum slightly for jewellery use. Unique to platinum is its whiteness, its strength and very long durability and a marvelous silvery like patina only time and continual wear will bring. The whiteness of this precious metal is the best choice to set an important diamond of high colour (DEF range) and will also enhance the colour of some lower colour grades (IJK). Conversely, LM and lower colour ranges may appear to ‘pull more colour’ in contrast when set in platinum. Working in platinum requires a higher level of skill and experience. The whole procedure must be done in a near sterile close environment since minute gold filings or other impurities on tools or workbench can contaminate the finished platinum product.

Anytime you see new platinum jewellery with a high mirror finish, add on many hours of labour intensive polishing to

achieve this result. Platinum takes a lot longer to burnish and bring to a bright

mirror-like finish.

Platinum is the most upscale, durable and fashionably timeless precious metal – that with the benefit of talent and skill – creates the world’s most important jewellery.

Diamonds are forever and so is platinum.

IN THE 18TH CENTURY, PLATINUM'S RARITY

MADE KING LOUIS XV OF FRANCE DECLARE IT

THE ONLY METAL FIT FOR A KING.

WHAT IS PALLADIUM? Palladium is a rare silver-white metal that occurs in a pure state in platinum ores and in the combined state in Canadian nickel ore. Palladium is both ductile and malleable although more prone to attack from common acids than other platinum metals. It is fairly reactive chemically and readily forms metallic compounds. It is not too often seen in jewellery but may been alloyed with 18 karat white gold. It is important that the goldsmith knows this metal is laser welded as opposed to traditional soldering methods.

PLATINUM IS TRULY THE ULTIMATE

PRECIOUS METAL: • VALUABLE

• STRONG

• LONG WEARING

• 95% PURE

• VERSATILE

• PRESTIGOUS

• Melting Point: 1768ºC (3190ºF). • Production: Each year 88 tons of platinum are made into jewellery. • Properties: Catalyst, hypoallergenic, resistant to heat and acids. • All precious metals can scratch, and platinum is no exception. However, the

scratch on platinum is merely a displacement of the metal and none of its volume is lost.

• Platinum is much more rare than gold and silver. Platinum is 30 times rarer

than gold and is found in very few places in the world, mainly South Africa and Russia, and to a lesser extent in Zimbabwe, Canada and South America.

• Every year only 88 tons of platinum are made into jewellery, compared with

2,700 tons of gold. It takes eight weeks and 10 tons of ore to produce one single ounce (31.1 grams) of platinum, whereas five tons are mined to produce the same amount of gold. There are also fewer platinum mines. For every 10 gold mines there is just one platinum mine.

• Pure platinum metal is often combined with other members of the platinum

metals group including, iridium, palladium, or ruthenium, to add strength. • Rhodium, another platinum member, is reflective and bright and is used to

plate gold.

OVER TIME, PLATINUM DEVELOPS A NATURAL PATINA THAT MANY

PEOPLE PREFER OVER THE "JUST POLISHED" LOOK.

REMOVING THIS DISTINCTIVE

PATINA CAN SOMETIMES AFFECT THE CHARM OF AN AGED

JEWELLERY ITEM. HOWEVER, REPEATED POLISHING OF PLATINUM DOES NOT REMOVE

MINUTE AMOUNTS AS WHAT HAPPENS WHEN POLISHING

KARAT GOLD. THE PLATINUM IS ’RE-POSITIONED’ WHEN POLISHED.

Platinum’s rarity as a metal has caused advertisers to

naturally associate it with exclusivity and wealth.

“Platinum” credit cards have greater privileges than

do "gold" ones. "Platinum awards” are the highest possible, ranking above

gold, silver and bronze. For example, a musical album

that has sold more than 1,000,000 copies, will be

credited as "platinum”.