Gold artifacts have been dated as far back as 4,000 BC in the Balkans, however it is thought that gold began to be used by artisans a few thousand years further than that. In Ancient Egypt gold was quite common around the Nile, it was in Egypt in fact that the first gold production and mining began.
Copper and gold are the only two pure metals that are not white or greyish in colour. Gold is the only non-white precious metal on earth.
Gold was treasured by ancient civilisations. To the Egyptians the fiery brilliance of gold symbolized the sun god Ra, while to the Incas gold was the sweat of the sun.
Gold has been featured in many myths, legends and fairytales. Case in point being legendary Trojan War, which may have been caused by a golden apple given by Paris, the Prince of Troy, to Aphrodite. She in turn permitted Paris to kidnap Helen, wife of Greek hero Menelaus. This resulted in war.
Fine gold equals 24ct. One carat is one twenty-fourth or 41,66 parts per thousand parts. This means that a 9ct alloy has 37,5% fine gold in the alloy ( 9/0.24).
There is no such thing as white, red, rose, pink, green or purple gold. Gold is always yellow in colour. However, the colour of the gold can be altered by adding differently coloured alloys to the mix. The lower the carat, the more alloy can be added, the bigger the intensity and the range of colours that can be achieved.
When a client brings in old gold, he/she expects to be compensated for the gold. It is not possible to give the client the full amount because:
COLOUR DIFFERENCES: 18ct white gold alloys have a slight yellowish tint and are rhodium plated to produce a white look. This white gold layer wears off with time. When this happens, the item needs to be replated. Platinum, on the other hand, is a white metal and does not need plating.
TENACITY: White gold is slightly brittle and white gold claws will not last as long as platinum ones. Platinum is quite hardy and does not abrade easily.
HARDNESS: Platinum indents more easily than white gold.
WEIGHT: Platinum is much heavier than white gold.
PRICE DIFFERENCE: Hand-made platinum items can cost three times more than a similar item made in 18ct white gold.
Palladium and Platinum’s history are interconnected. This is because “Native Platinum” is actually an alloyed mix of platinum group metals, which includes palladium. Platinum and Palladium share their early history, as they weren’t separated from each other for quite some time. In 1803, William Hyde was able to separate Palladium from crude platinum ore.
Palladium was first used for jewellery during WWII when platinum was reserved for military use. In the 21st Century, jewellery designers were searching for a less expensive alternative to platinum and developed palladium alloys. These alloys are workable, hypoallergenic, tarnish-free and do not need rhodium plating. Various palladium alloys were produced. The most popular alloy contains 95% palladium and 5% ruthenium.
Palladium is a platinum group metal. It is the lightest of the group and has the lowest melting point.
Palladium is especially popular and attractive in jewellery because:
Platinum and platinum group metals are purified from “Native Platinum”. It is highly doubtful that ancient civilizations recognized Platinum as a separate body from “Native Platinum”. Traces of Platinum have been found in Ancient Egyptians artifacts, the best known example is a seventh century BC box that has a strip of platinum set amongst hieroglyphics. The strip has been hammered out in the same fashion that Thebian craftsmen treated silver, it is mostly likely treated in this fashion as it was mistaken for silver.
Knowledge of the white metal platinum only spread through the world a few hundred years ago. Even though the South American Indians worked with it some 1000 years ago, the news of the metal only reached Europe during the Spanish conquest of the new World during the 15th and 16th centuries. However the Spanish deemed Platinum a nuisance as it interfered with their mining of gold.
Nowadays we realize that Platinum is a rare and expensive metal. It has perfect properties that make it suitable for jewellery. It is a highly malleable, silvery-white metal that is extremely resistant to oxidation and corrosion.
Fine platinum is very soft and has to be alloyed to make it suitable for hand manufacturing. In South Africa, there are two alloys available for hand fabrication – a platinum/copper alloy and a platinum/ruthenium alloy. Both alloys consist of 95% pure platinum and are hallmarked “PLAT”.
Silver has been used for thousands of years in trading, monetary systems and as decoration. Its value was secondary to gold. Silver has been known since ancient times. It has been thought that silver was separated from lead as early as 4th millennium BC. Proof being that silver is mentioned in the book of Genesis, slag heaps have been found in Asia Minor and on the islands of the Aegean Sea.
Silver is the most common of the precious metals and has working qualities close to those of gold. Although it is resistant to many chemicals, it can be damaged by nitric acid and sulphur. The latter causes dark stains that silver items seem to develop over time. Being a soft metal, silver items scratch easily, but the scratches have soft edges, and, in time, they blur to give the metal a pleasantly aged appearance called “patina”. Collectors of silverware prize patina.
It is thought that silver was discovered shortly after that of copper and gold. To date the oldest reference of silver can be found in the book of Genesis. To the Egyptians gold was the perfect metal and so they gave gold a circle as a symbol, as silver was the closest to gold in perfection it was given the symbol of a semi-circle. This semi-circle symbol later grew to be known as the symbol of the moon, no doubt due to the similarities of shining silver and the glowing moon. The Inca’s believed silver was the sweat of the moon.
Silver just like gold was considered sacred by ancient civilisations. It was used to cure infection, pay debts, to decorate and even as utensils in wealthier homes.
In European folklore silver is recorded as an antidote to certain maladies and even monsters. It was believed that silver repelled vampires and werewolves were easily put to death by a silver bullet or weapon made out of silver. The use of silver to cure infection dates back to Ancient Greece and Rome. While in the Middle Ages it was used to disinfect water and to treat burns and wounds.
Because pure silver is quite soft, it is mixed with copper to produce harder alloys that have various uses.
Stainless steel was first discovered in 1913. Harry Brearley and team were busy researching and experimenting with different types and qualities of alloys. He found that the steel gained an exceptional resistance to acid corrosion when alloyed with a minimum of 10.5% chromium. The chromium in the alloy forms a thin invisible layer of chromium oxide when exposed to oxygen. This layer prevents the metal from rusting. Even when the surface is scratched, the protective layer quickly reforms.
Today, stainless steel has become a much-used metal in the production of men’s jewellery especially. It is widely used for piercing jewellery and watches are often produced in stainless steel.
Titanium was originally named gregorite, after the British chemist, Reverend William Gregor He discovered it in an inclusion in a mineral in 1791. Gregor noted the presence of two metal oxides in the mineral, one being iron oxide and the other he was unable to identify. German chemist M.H. Klaproth independently rediscovered the oxide in 1793. He named it Titanium after the Titans of Greek mythology. In 1797 he realized that Gregor’s earlier discovery was the same as his Titanium. Titanium was only successfully isolated in 1910 by Matthew A. Hunter, through a rather laborious and costly exercise.
Although its extreme hardness and high melting point make titanium a difficult metal to work, modern technology has succeeded in producing jewellery (especially wedding bands) at a highly competitive price and with a unique look.
Titanium, a greyish metal, can be inlaid with precious metals such as gold, platinum and silver. When treated with heat, its surface oxdises into a magnificent spectrum of colours. This feature has made it a popular metal for ladies’ jewellery.
Titanium is used in its pure and alloyed state to increase strength.
Positives of titanium jewellery:
Titanium jewellery drawbacks:
In Swedish the word Tungsten means “heavy stone”. It’s other name, Wolfram, is derived from the name of the mineral Wolframite. This is where Tungsten’s chemical symbol W comes from.
The metal Tungsten was first isolated by two Spanish chemists, the de Elhujar brothers, in 1783. The metal can be isolated from minerals wolframite, scheelite, huebnertie and ferberite. Tungsten is promoted as the only rare and exotic metal that is permanently polished. It is often said about a Tungsten ring that “The polish of your ring will last as long as your commitment to each other.” The heavy weight and lasting polish of a tungsten ring make it special and sought-after by those who want a unique item. It is ten times harder than 18k gold) and requires special working methods that normal goldsmiths often do not have.
A thin layer of rhodium, a member of the platinum family, is applied over white gold, silver or copper and its alloys in order to enhance the shine and durability of the jewellery item.
Rhodium plating is not permanent and will wear off in time. However one can easily re-plate the jewellery item. Re-plating is relatively quick process. White gold know to yellow with time if not plated with rhodium. The original white gold colour can be restored if rhodium plated.
Plated, refers to a piece of jewellery that is made from metal such as copper or silver and then covered through an electroplating process with a thin layer of precious metal (often gold). The jewellery is usually hallmarked only based on the silver content and not a gold hallmark.
A good example of plated jewellery is costume jewellery. The plating will rub off in time but all can be restored through re-plating.
Bonded jewellery is created when gold is bonded through heat with the original metal, often silver. The bonded product has a thicker layer of gold that is less likely to wear off in time.
A hallmark is a mark or series of marks struck on a precious metal item – platinum, gold, silver and palladium. Hallmarking differs from country to country.
South African popular caratages:
Platinum: Pt950; Pt900; Pt850
Gold: 9ct or 375; 18ct or 750
Silver: SIL, S925 or 925; S835 or 835.