Key points: 

1.  Pure gold is measured as 24 karats, and is too soft for everyday wear
2.  Gold is alloyed with a mixture of other metals such as silver, copper, nickel, and zinc to give it strength and durability
3.  The colour of gold is determined by the type and percentage of metal alloys added
4.  18 karat gold is a mixture of 75% pure gold with 25% other metal alloy
5.  Gold can last virtually forever - it does not rust, corrode, oxidize, or tarnish in any way

The allure of gold jewellery is just as prominent today as ever before. Throughout history, various cultures feverishly sought gold for many reasons. The ancient Mayans used gold as sharpened weaponry (even though it’s not the sturdiest of metals), while the Spaniards viewed gold as a treasured commodity. Different cultures saw gold through a particular filter that allowed it to be valued for either religious, war-like, or monetary reasons. Today, gold is primarily used for adornments (as well as currency) all over the world. In fact, wearing of gold as “personal decoration” is one of its oldest applications in history.

Gold is not only found within cosmetic adornments, but is also used for architecture as well. Numerous cities pride themselves in having towering skyscrapers, glimmering avenues, and entwined walkways that actually have gold tinted into their infrastructure. Furthermore, gold is also used for modern dental procedures, medicine, computer parts, space shuttle appliances, as well as homemade appliances.

According to the periodic table, the symbol of gold is Au (Aurum). The word “Aurum” is Latin that loosely translates into “Shining Dawn”. Ever since the first discovery in 5000 B.C., the fever to mine gold has spread across 60 countries.

Gold jewellery has four key characteristics which has made it treasured for eras: colour, rarity, durability, and workability. Taking time to understand these characteristics will give you a more detailed insight into gold and consider whether it is a suitable metal for your jewellery.

Colour

Pure gold is "yellow" in colour. However, gold is often mixed with other metals resulting in different colours. In jewellery, the most prominent colours that are used are “yellow”, "rose" and “white” gold.

Yellow Gold - Pure gold is 24 karats and is too soft for everyday wear. Jewellery is often made from 18 karat gold which is a mixture of 75% pure gold with 25% other metal alloy to enhance its strength and durability.  

White Gold - White gold is a mixture of pure gold with white metals, such as pladium or silver. For instance, 18 karat white gold contains 75% gold and 25% of white metals. Given the composition, jewellery made from these metals has a slight yellow tinge. To enhance the whiteness, almost all white gold is plated with a shiny white metal called rhodium. Through ordinary wear, this rhodium plating may wear off over time, revealing the original metal colour. Re-plating may be done by a jeweller to restore the whiteness of the jewellery.

Rose Gold - Rose gold gets its beautiful pink colour from combining gold with a larger proportion of copper in the metal alloy.

Other colours of gold, which many people are not aware of, are “blue”, “black”, and “purple”. These colours are produced from either one of two processes. The first process is by adjusting the formations of the “Intermetallic Compounds” (which are special gold compounds that help give the gold its tint). The other process is called “Patination of Gold” which is basically defined as layering colour on the surface on the gold piece. “Purple gold” (or violet gold) is made by aligning aluminum and gold compounds into a particular ratio that combines the tint to reflect a “purple surface”. The density of the actual “gold metal” is 79% and can sometimes be considered as 18K gold. Creating “blue gold” is fundamentally the same as “purple gold,” but instead the alloys that are used are “gold” and “indium”. If it’s manufactured by a certain ratio, these alloys will give off a bluish hue. Lastly, “black gold” is created by a handful of different procedures. Sometimes the controlled oxidation of gold that has chromium or cobalt on the surface seems to manifest a “black” coating. Another method is “electrodeposition” with the use of ruthenium and black rhodium. Finally, the treatment of using amorphous carbon with the help of the “Plasma Assisted Chemical Vapor Deposition” procedure has also proven to be effective in making black gold as well.

Rarity

Gold is found in many areas of our planet. The prime location on where to find it is deep within the Earth’s crust. Gold is very rare and requires a lot of intensive labour in order to find a single ore. It usually takes hours of mining before an ounce of valuable gold is even found. Naturally, this is what makes these metals to be considered so precious. There is actually a very small amount of gold available in the world today. It is thought that if you take all the gold in the world and compressed them together, you will get a cube that’s only 18 yards in diameter.

A vast majority of gold that is mined from the Earth comes from a large operation that’s currently stationed in North Dakota. There has only been about 88,000 tons of gold mined from the Earth since its discovery and many experts believe that there are tons yet to be discovered. If one manages to find a “gold nugget” it will be considered extra valuable than the actual metal of gold itself. Finding “golden nuggets” is a novelty that many people still embrace. Gold has incredible stability with its chemicals and is also highly resistant to oxidation as a well as corrosion. Because of this fact, gold jewellery is perfect for being worn as long-lasting adornments and should be considered the most precious metal of our time.

Durability

As mentioned before, gold can last virtually forever. It doesn’t rust, corrode, oxidize, or tarnish in any way. Essentially, this is why gold is considered as the perfect companion with one’s diamond for their engagement ring. Diamonds and gold go hand-in-hand with their chemical stability, sturdy demeanor, and eye-catching properties. The theory of the incredible longevity of gold has been proven time and time again simply by digging up ancient tombs of royal families and emperors.  The unearthing of a famous Pharaoh (King Tut) that died over 3,000 years ago surprised archaeologist because all of his golden riches still remained perfectly intact as the day he was mummified with them.

Workability

Gold has one of the best working qualities making it an ideal precious metal for fine jewellery. Gold is soft and malleable, allowing it to be alloyed with other metals to produce variations in colour and desired effects. Gold can be stretched or flattened into shape, it can be melted and re-used over and over again.