Gold colours and carat weight explained
Gold is a chemical element it has the chemical symbol Au from Latin aurum . In its pure form, it is a bright, slightly orange-yellow, dense, soft, malleable and ductile material. Gold is the king of all metals.
The bright yellow colour of pure Gold is wonderful. Here is an image celebrating the month of November and the yellows and golds of Autumn, which are echoed by months birthstone yellow Topaz.
The Origins
The earliest recorded metal found and used by humans appears to be gold. Small amounts of natural gold were found in Spanish caves and used during the late Paleolithic period around 40,000 BC.
Humans have cherished gold for thousands of years. Gold artifacts probably made their first appearance in Ancient Egypt at the very beginning of the pre-dynastic period. Gold remains a symbol of beauty and luxury today. Gold's beautiful colour, durability, and rarity make it a truly timeless choice for jewellery, whether for everyday wear, or special occasions.
Occurrence
On Earth, gold is found in rock formed from the Precambrian time onward. Native gold occurs as very small to microscopic particles embedded in rock, often together with quartz or sulfide minerals such as 'fools gold', which is iron pyrites. These are called lode deposits.
The metal is also found in the form of free flakes, grains or larger nuggets that have been eroded from rocks and end up in alluvial deposits called placer deposits.
photo credit Marko Ivanov unsplash
Culture
In popular culture gold is a high standard of excellence, often used in awards. Great achievements are frequently rewarded with gold, in the form of gold medals, gold trophies and other decorations. Winners of athletic events and other graded competitions are usually awarded a gold medal. Many awards such as the Nobel Prize are made from gold as well.
photo credit George Pisarevsky unsplash
Gold mining
We have mined over 187,000 tons of gold to date. That is a cube of 22m by 22m and 50% of this has been used in jewellery.
Why gold is so good for jewellery
Gold is a metal like no other. It's the second least reactive of all metals, meaning that in its pure form it won't tarnish, rust, or corrode. The least reactive is platinum, but only by a very small margin.
This makes gold a perfect choice for jewellery; metal that lasts a lifetime. Gold is naturally found in a pure form, unlike many metals that need intensive processing to extract.
Gold carat weight
The weight of gold is measured in troy ounces (1 troy ounce = 31.1034768 grams), however its purity is measured in ‘carats’.
‘Caratage’ is the measurement of purity of gold alloyed with other metals.
24 carat is pure gold with no other metals meaning 24 out of 24 parts of it are gold.
Gold alloys
When gold is alloyed with other metals to make it more durable or to achieve different colours, the carat rating decreases.
- 18ct gold: 18 parts gold, 6 parts other metals (75% pure gold).
- 14ct gold: 14 parts gold, 10 parts other metals (58.5% pure gold).
- 9ct gold: 9 parts gold, 15 parts other metals (37.5% pure gold).
You will very rarely see jewellery made in 24ct gold, and even 22ct is quite rare. This is because the purer the gold, the softer the metal - and soft metal is not ideal for making jewellery. Instead gold is alloyed with other metals to make it stronger and more suitable for different uses, including jewellery.
The minimum carat weight for an item to be called gold varies by country.
In the US, 10 carat is the legal minimum accepted standard of gold caratage, 14 carat being the most popular.
In France, the UK, Austria, Portugal and Ireland, 9 carat is the lowest caratage permitted to be called gold. In Denmark and Greece, 8 carat is the legal minimum standard.
How the carat affects the colour and durability
18ct and 14ct are the most common purities you'll see used to make jewellery. These also have a brighter yellow, which is lost in lower carats of gold, with 9ct gold being a fairly light yellow.
9ct Gold: Affordable but light Coloured
9ct gold contains 37.5% pure gold, so it will be durable and retain the value of its gold content. It's the most affordable type of gold. However, it has a paler duller colour than higher carats and is less valuable. Consider 9ct gold for budget-friendly jewellery, especially for everyday wear or for children.
14ct Gold: A balance between the two
14ct gold, with 58.5% pure gold, offers a great balance between durability, colour, and affordability. It's long been a popular choice in the USA and less so in the UK.
I think 14 carat gold will become more popular in the UK as the price of gold is rising.
18ct Gold: Vibrant & Valuable
18ct gold (75% pure) is known for its rich colour and luxurious feel. It's ideal for high-quality investment jewellery. It's also a popular choice for wedding and engagement rings. While it is more expensive, the investment and bright colouring may well be worth it for pieces you'll wear and treasure forever.
22ct & 24ct Gold: Pure & Rare
22ct gold (91.6% pure) and 24ct gold (99.9% pure) are rarely used in everyday jewellery. They are too soft for regular wear and are more commonly seen in fine jewellery which will see very minimal wear and handling. However, you might see 24ct gold used in gilding or plating.
Gold Colours: Yellow, Rose & White
Gold comes in a range of beautiful colours, including:
Yellow Gold: The classic warm glow from the colour of pure gold, which is especially vibrant in higher carats.
Rose Gold: Pure gold alloyed with copper to create a pinkish or reddish hue. Rose gold, it can be a beautiful and striking alternative to more common yellow gold. Rose gold is sometimes called pink gold or red gold, with varying intensities of colour, depending on the alloy used.
White Gold: A yellow white or brown white metal, made of pure gold most often alloyed with palladium or nickel and is often plated with rhodium commercially for a bright white finish. I never Rhodium plate white gold unless as it wears off and I like the colour of 9 and 18ct white gold. 9ct is a pale yellow white and 18ct a slightly brown white.
Combining yellow and white gold
I have made many pieces over the years combining two colours of Gold which is very effective. Here is a diamond ring commission to show the nice colour contrast of the 18ct yellow and white gold.
Melting mixed gold together for recycling
When I am doing commissions using Gold from unwanted jewellery, often the customer has a mixture of different carats and different colours of gold. If they want to use it all and have it melted all together the colour it makes is often subtle and very beautiful.
Here is a mans 'Shark Skin Signet' ring commission made with a mixture of old yellow gold rings, belonging to his late father. There was not enough gold to make the ring so fresh gold needed to be added so white gold was added to the melt as he preferred the colour of white Gold. He was so happy with the result it is a really lovely and subtle soft pale yellow gold.
Here is another ring commission which was made from some old gold fillings in teeth ! This was a first for me! Other Gold was added to the cast and the resulting rings for her and her daughters are really pretty.
Gold commissions
I have mainly focused on making my work in silver as my wish was to make affordable jewellery. Although my initial love was for silver, I now appreciate gold just as much. I make most of my commissions in gold, but I use gold vermeil on my ready to wear pieces, in order to keep the cost down.
I am thinking back to the largest item I have ever made in gold. It was this 9ct gold cuff bangle. A customer wanted me to make my version of a silver bracelet that his wife wore and loved. I made this piece in June 2017, using 9ct yellow gold. I loved making this special piece, firstly I had never made anything like it before. It was also a memorable experience, as I made it in my friend Joanne's workshop in Essex. I spent a few days working alongside her. It was such fun to have company and catch up, as we used to do shows together in the 90's.
GOLD - The beauty and variety of this precious metal and the way it has been shaped and crafted by countless craftsmen and women has, like fire, fascinated humans as long as we have inhabited this planet