Gold is one of the most extravagant precious metals of all that we can find in nature: it is accessible but scarce, and it is this detail that has led it to be coveted by humanity. However, due to the need and tastes of each client, it is currently possible to differentiate different types of gold. Do you know how this noble metal can be classified?
Types Of Gold According To Color
Gold is a brilliant and captivating natural metal in a deep yellow color. However, in jewelry, it is possible to find different types of gold for rings and other pieces that favor a wide range when choosing the jewel that most identifies you.
Yellow gold is usually found in pieces made of pure gold, whose material is not mixed with other metals. Its high quality and color not only increase the category of the piece but also favor greater durability over time.
Very common in wedding rings, white gold results from combining pure gold and other metals such as palladium, silver, and nickel. You can see a fabulous example with our 18k white gold and diamond wedding band.
Greenish-yellow gold is the product of mixing silver and yellow gold, to which cadmium or copper is also added. The result will be a deeper or lighter green color depending on the number of metals used in this combination.
It is not usually used nowadays since cadmium can cause allergies.
Rose gold and red
Although showy, the less frequent types of gold in jewelry are red and pink gold, which are obtained according to the amount of copper used in the mixture. The pieces made with these types of gold are usually combined with white or yellow gold, giving rise to two-tone jewels.
The jewels made with this material have an electrolytic bath of gold or rhodium. It adds a lot of shine to the pieces but could be of better quality since that bath is lost over time. They are not considered gold jewelry and are framed in costume jewelry.
Also, if at any time you have wondered why one gold is more yellow than another, this is precisely due to the amount of gold with which the piece is made.
Types Of Gold According To Carats
On the other hand, gold can be classified according to its purity, in which case we refer to the carats. The greater the number of carats, the greater their quality and value.
Among the most valuable types of gold, we find 24-karat gold, which boasts 99.9% purity. Gold bars are the perfect example.
However, “pure” gold is very soft and is not suitable for making jewelry; for this, it is mixed with other metals that give it properties that make it malleable and resistant.
18 karat gold
This class comprises 18 parts of gold to 6 parts of other metals, often silver and copper. In this way, 75% purity is achieved, becoming one of the most used types of gold in jewelry.
14 karat gold
It receives the name “low gold” and is characterized by a purity of 60% since it has 14 parts of pure gold and ten parts of other metals.
It is a type of gold widely used for jewelry in countries such as the United States; however, it must be taken into account that the amount of gold it contains is very low compared to the “gold of law”; therefore, its value is lower.
12 karat gold
12k gold comprises 12 parts of gold to 12 other metals, reducing its purity to 50%.
10 karat gold
It receives its name due to its composition —10 parts of gold and 12 parts of other metals. It is only 40% pure gold, so it is considered low-quality gold.
What is the difference between 24k, 18k, and 9k gold?
To answer this question, we have to talk about the purity of gold, its composition, and it is an expression in carats “k.”
Pure gold = 24k = 1000 thousandths = 100% Gold
Pure gold cannot be used in jewelry because it has no suitable consistency. 24k gold is too soft; they would break easily. Jewelers work with an alloy in which we mix pure gold with other metals.
And what is the color of gold due to?
This is where the other variable we discussed at the beginning, the Gold Alloy, comes into play.
Pure or 24k gold is always yellow. But you already know that for the gold that we work in jewelry, we need to mix it with other metals. It is in this “magic alchemy” that the secret of its color lies.
Why mix gold in alloys? There are several reasons to do so:
- Achieve greater metal hardness
- Get a wide range of colors
- Reduce cost per gram
The metals that can be used to mix with gold are very varied, each with different properties.
How often will we have to roll the jewel?
Well, it will depend on your use, your PH, and the type of jewel. For example, earrings with little friction with the skin will take years before you need to rhodium them. However, some white gold wedding bands will have much more frequent maintenance if you want to keep them as bright as the first day.
How can we know if a jewel is a gold?
Those of us who are dedicated to the world of jewelry care for our customers; are aware of their trust in us. You will have no doubts if you buy a new piece in a trustworthy jewelry store. They will inform you of all the details you need to know.
If you buy online, ensure it is a reputable company with a track record, not a newcomer. Nobody offers “duros a peseta” and even less in a sector where the markets control the price of raw materials.
When in doubt about the authenticity of a jewel, it is best to go to a gemologist.
So that you understand the importance of dealing with a specialist, this is what we do when you bring a jewel:
- In visual analysis: we see the piece’s color and weigh it by hand. Gold is heavier than silver, and an expert jeweler can only give you information by holding the piece.
- Search for official brands: what is called the contrast of the piece. The stamp marks whether the jewel is 750mm gold or 925mm silver. It is usually hidden and requires a 10x magnifying glass. If the jewel is from before the 1950s, likely, it is not minted, but that does not mean that it is not made of gold.
- The next step is to rub the jewel with a touchstone. It is made of a porous material to which small particles of the piece remain attached. Once the sample is obtained, the jeweler adds a few drops of a chemical solution (nitric acid) that breaks down all the materials but leaves the gold intact.
How to know the purity of the gold in a jewel?
The touchstone and the acids will allow us to analyze the purity of the gold used in the jewel.
We take the jewel and scratch with it on the touchstone. We always try to do it in the least visible area to avoid damaging the jewel. We will see that a greyish stripe remains on the stone. We start with the acid for 18k gold. We pour a drop on the mark made on the touchstone. If the mark is gone, the jewel was not 18k gold.
To find out if it is from another alloy, we will repeat the process and use another acid to check if it is 14k. And so until we know the metal used in the jewel.
It is a process that takes a few minutes, and acids must be handled very carefully since they are toxic.
We have explained the process that is usually done in a jewelry store.
Today some machines measure fluorescence with X-rays to quickly verify the authenticity of jewelry and analyze the composition of gold and precious metals. Companies in charge of melting and refining metals use these devices.
In conclusion, although each of the types of gold has its particularities, the truth is that the quality of the piece will be determined by the combination of the purity of the gold —that is, the carats and the metals, and the color.