24k, 24k Magic. What's thats sound?!
24k/24ct is the purest form of gold. And as a result it is not that durable. It is incredibly soft, so when Gold is used in jewellery it is mixed with other alloys to make it more durable amongst other reasons. So, as you are now going to be mixing Gold with other alloys, how can you tell how much is actually gold?
Hallmarking is one of the first forms of Trading Standards. Records can be traced as far back as the early 13th Century when the first official standards of Gold and Silver quality were first decided. In 1300 AD, King Edward I decreed 'no silver was to depart the hands of the workers' until it has been assayed (tested) and marked with the leopards head if it passed, the leopards head being the symbol on London. Interestingly, this was when 92.5% was decided to be the acceptable standard of Silver, which is still the case to this very day (Sterling Silver).
In 1973, The Hallmarking Act was introduced. The 39 page document outlines the current British legislation of all items made from precious metals. In this post we are going to focus on Gold Hallmarks, as there is a lot of information to cover if we include all alloys!
Today, English Gold Hallmarks are divided up into 9ct & 18ct. Other hallmarks such as 22ct have been used in the past, but we now generally just stick to 9 & 18. Which makes it nice and easy to understand the difference between the two. We will start with 18ct as the example. 18ct is stamped 750. This means out of every 1000 pieces, 750 of them will be gold. Imagine it as a cake mixture...
750 / 1000 = 75%
So, 9ct is just simply half this. Out of 1000 pieces, 375 of them are gold. As you can see in the table to the left, there are other carats that the UK have had in the past. All you need to do is move the decimal place one place to the left to see what percentage of Gold it is.
You can also see 4 other marks accompanying the carat mark. From left to right we have,
SAO: Makers mark. Simply put, a small logo of the company or person who made the item of jewellery. We have our own Makers Mark, WRC.
Rose: This is the Assay Office. Each Assay Office have their own mark, when deciphering the hallmark, this is generally the first thing you will look at after the Carat mark. The Rose is the mark of Sheffield, which is one of the four remaining Assay Offices. The others are London, Birmingham and Edinburgh.
Crown: This is the fineness mark. Each precious metal has their own mark, in the case of gold it is the Crown.
The letter G: This is the date letter, when the item was made. Each Assay office has their own date mark for each year, after one cycle a different font is used to avoid confusion with previous letters made by that assay office.
It is very interesting when older pieces come in to us, items which have been passed down each generation. When we then have a look at the hallmarks, it's great to hear when customers say 'That sounds about right, that's the year my grandparents got married'. All of these pieces have a story and it's great to hear them and share the enjoyment that jewellery gives us.
Next time we look at 9ct Gold vs 18ct Gold, a subject which is quite blurry!