With so much gold circulating the globe, it’s not a bad idea to make sure you are confident in the karat amount you have. As a buyer or seller, get in the habit of checking the quality of your gold, so you are not taken advantage of. Here are some ways to do so.

The value of gold is determined by its karat rating. An object made from 18-karat gold will cost you more than the same object made from 9-karat gold. An experienced jeweler will be able to guess the value of an item just by the naked eye, but they also use tests to determine the karat rating of gold. Knowing how a jeweler determines the karat value will help you.

Karat (spelled “carat” in the UK) is a measure of the fineness and quality of gold. That is the amount of gold about other metals that make up an object. In US and Canada, the most frequently used karat values are 14 karats and 18 karats (meaning 58.5% and 75% gold respectively). In the UK, 9, 18 and 24 carats gold are the most frequently used alloys.

There are many variations in the color of gold, ranging from white, yellow to red. Pure gold is a deep golden yellow. In its most perfect state, it is very soft, and although this makes it very easy to work with, for everyday use a harder metal is needed. Gold is therefore combined with a base metal, commonly copper or silver, to form an alloy.

What is often referred to as “white gold” has a high amount of silver in the alloy. Similarly, “red gold” contains a lot of copper.

A gold assay test shows the percentage of gold compared to others metals in an item. It is an analysis of value rather than of quality. Expensive materials can be poorly manufactured and, similarly, cheaper metals may have been worked with exquisite craftsmanship. An assay or hallmark is an objective chemical test.

Hallmarks show that an assay test has been carried out on the gold object to confirm its authenticity. The reliability of the hallmark depends upon the country of origin. State-controlled assay offices imprint a mark onto the gold showing the year and place of assay together with the percentage of gold found, or the karat rating. The hallmark is tiny, so you may need a magnifying glass to see it clearly. Many jewelers use a loupe, a special magnifying glass used in the jewelry business.

If the hallmark is clear and readable, this is the quickest way to check the gold content of an item. However, over time some of these marks can become worn, and some may have been tampered. So how do dealers determine how much a gold item is worth if the karat mark is indistinct or missing?

There are different ways to test the state of your gold jewelry. If you do not want to use a jeweler, you can use a take home test. The kit consists of some solutions of dilute acid and a touchstone. The touchstone is made of a dark acid-resistant rock such as slate. The jeweler rubs the gold object gently across the stone so that it leaves a streak mark. He or she then applies the acid solutions in turn to the mark. The higher the gold content of the metal, the less of it will vanish when acid is used.


Test Comments
Look at the color The deeper the orange-yellow color, the higher the karat.
Check the hallmark Are the assay marks clear and are they from a country that you can trust?
Carry out an assay test Take care. Wear protective clothing as you will be handling acid.


One of the reasons why gold is such a prized metal is that it does not react to air. Thus gold does not rust like so many other metals.

Gold also does not cause skin irritation if worn. Discoloration or rashes on the skin next to the jewelry indicate that the gold has been tampered with and is not pure.

Always be sure to know exactly what you are selling before you make the final decision and sign on the dotted line. Knowing what you are getting out the deal is crucial for a successful transaction.