Gold: Covering the Basics of a Precious Metal

Gold is a precious metal. This is something we all know. However when it comes to practical use, gold in its pure form is generally unusable. God as a precious metal, if it becomes a viable source for commercial and industrial application is often combined with other metals: usually alloys like copper, silver, zinc and other select metals that enhance, improve or strengthen its features.

Ternary plot of different colours of Gold-Silver-Copper alloys

Original image: Metallos, CC BY-SA 4.0, via Wikimedia Commons

Gold Carats

A simple way to understand the uses of gold is to see how it is used in the jewellery industry. Pure gold, without any other metal additions, is too soft, and almost impossible to shape into a sturdy form that can withstand pressure, scratches etc. One is likely to have heard about 14K vs 18K distinction when it comes to gold jewellery. One that is supposed to affect the quality, usability and importantly the price of the jewellery. The difference between gold carats is determined by the percentage of metal alloys that are added to pure gold to alter its condition in a certain direction.

Rose Gold

Rose gold is made by combining pure gold, with various levels of copper and silver. With copper being the dominant metal addition. Rose gold is mainly used in jewellery. Hence the addition of other metals is determined by the expectations of the jeweller: who may be seeking a deeper or lighter rose colour or looking to make the ‘gold’ sturdier. For example in an 18K rose gold option, the combination is likely to be: 75 gold to 25 copper. As depicted in the image above, the greater the percentage of copper, the more reddish or rose-coloured it would become. In 14K options, the split between gold and copper is more equal. With gold holding a slightly higher percentage. Usually over 55 per cent.

White Gold

First off, white gold is made of normal gold. The ‘white’ is the result of the addition of other metal alloys like nickel. However, due to its character as a potential irritant, white gold that results from combining nickel is often plated with rhodium. Once again the percentage of nickel and other metal alloys that mixed differs with regards to the expectations of the jeweller. As the image explains, nickel is not the only metal of choice to lighten its colour. Silver is another metal candidate that is often used to lighten gold.

Yellow Gold

This is the basic gold. Gold in its natural form is of a yellowish colour, with a light sheen. The ‘colour’ of yellow in its pure form (24K) is of a darker tone. However in its purest state gold is basically unusable, owing to its delicate character. To harden it and to make it more durable, and suitable for jewellery, gold is often mixed with other alloys. Usually, the additions are copper and zinc. However, since the aim is to maintain the ‘gold’ colour, these metals are added in controlled levels, with a gold percentage at higher levels. Yellow gold comes in 14K, 18K, and in some cases 22K varieties. With the level of gold content increasing with each. In the image above, gold is at the top: which means the type of metals that are added varies. But the percentages remain fixed.

Secret Sauce

Gold is a widely used metal. Besides jewellery, gold has many applications in industry and other uses. So depending on the application, and demands the changes that are made to the metal will vary. This is notable in the jewellery industry. Where some jewellers will claim to sell you a certain kind of gold variety (e.g. white gold), that comes with special attributes: colour, durability, and other effects. The secret sauce, a stable in cooking, is also applicable in the jewellery and metal industry. As there are many combinations of alloys that can be added, and with it, so do the options for the innovative application.