"I'm in the process of designing a gold necklace, for everyday use. What effect will the karat of the gold have on its durability - and how much more will it cost if I go for a white or rose gold design?"
- Abbie, Bristol
"Karatage is the measure of how 'pure' a piece of gold is - with a scale going up to 24 karats (the table below shows some examples).
The remaining percentage of a gold alloy will be made up of other metals, such as silver, copper, nickel, palladium and zinc.
Gold is relatively very soft compared to these metals, and issues can arise in mixed-alloy jewellery items, since alloys with a lower percentage of gold in them will be tougher than the reverse.
For example, an 18-k pendant held by a 9-karat chain will likely wear down over time with frequent use, since the chain is harder and more durable and will affect the pendant via friction.
For this reason, I recommend using a single karatage for a design, although mixing the colours of separate parts is fine (e.g. a yellow gold chain holding a rose gold brooch). If you want to wear your item every day, it is more sustainable to use 18-karat gold or lower.
Higher karats of 22k and 24k are particularly effective for fine jewellery setting, and pairing with softer, more intensely coloured stones, such as emeralds - I'm a big fan of combining the rich colour of high-karat yellow gold with emerald's sea green hue and I think it is a stunning combination.
I wouldn't recommend these higher karats for everyday use, due to their softness and, especially in the current market, much higher price.
For coloured gold options, the price isn't too different. With 9-karat yellow gold as a base price, 9-karat white or rose gold will likely only be £1/2 more expensive per gram - overall price is chiefly determined by gold purity."
Neil Rayment is a Goldsmith-accredited fine jewellery and metalcraft expert with over 30 years of experience in the industry.
View Neil's breahtaking designs at his own site, here.
Do you have a question for Neil? Send him your queries at firstname.lastname@example.org for an answer!