Precious and non-precious metals in jewelry

Precious and non-precious metals in jewelry

There are various metals featured in the world of jewelry. A complete list would include not only precious metals (noble metals) such as gold and silver, but certain non-precious metals (base metals) such as copper, tungsten, iron, titanium, zinc, and nickel. 

To make informed decisions, it is important to understand what a piece of jewelry is made of. It is very rare to find a jewel that is 100% made of only one pure metal. What is sold as "gold jewelry" is really a mixture of pure gold with other metals. For example, 18k gold jewelry is 75% pure gold and 25% other metals such as palladium, silver, and copper. Another example is "sterling silver." It is a combination of 92.5% pure silver and usually 7.5% copper.  

Precious metals have certain characteristics that we admire, such as their shine. However, no metal has all the qualities necessary to make a lasting piece of jewelry, so we jewelers mix precious metals with base metals to match the characteristics of the metal.

Admiring the photos in this article, you will notice that most of the metals used in jewelry have a white or gray cast. Gold, which has a natural yellow color, and copper, which has a red color, are the exceptions.

I warn my readers that the article is quite long. If you are interested in a specific metal, I suggest "browsing" the article by looking for the title of the metal you are looking for.

precious metals

In jewelry, there is a clear division between precious metals and non-precious metals. A precious metal generally has the following characteristics:

• little reactive – so it is common to find the metal in its pure state in nature.
• high economic value
• bright
• ductile, meaning that metal can be worked relatively easily to change its shape
• rare in terms of limited quantity

Gold, platinum, palladium, rhodium, and silver are included in this category. These are the most common precious metals in jewelry. But there are other precious metals too: iridium, osmium and ruthenium. These last three have more applications in industry than in jewelry. 

base metals

While ductility is a desirable characteristic, certain precious metals are too soft and soft to hold their shape over time. Pure gold, for example, is easy to bend or sink. Other precious metals may be too brittle, hard, or easy to scratch. The precious metals are then mixed with base metals to adjust the characteristics of the precious metal.

Generally, base metals:

• react with other chemicals leading to corrosion
• they have cheaper prices

In fact, supply and demand have a lot to do with what is considered a precious metal. Aluminum, for example, was a precious metal despite being one of the most abundant metals on earth. In nature, aluminum is not found in its pure state. So until an industrial purification process was invented in the mid-19th century, aluminum cost more than gold. The French made aluminum jewelry with great ingenuity and skill.

Summary of the most important precious metals in jewelry

I am going to give a summary of the precious metals and the base metals that are used in jewelry. I hope to clear up the mystery of what a jewel contains. So when you go shopping, you can enter the store well informed and with more confidence. 

Gold

Possibly the metal most associated with fine jewelry, gold is a noble metal with little reactivity. So polished gold does not lose its shine easily and gold generally does not cause allergies. 

Pure gold has a brilliant yellow color. Unfortunately pure gold is very easy to bend and sink, so it needs to be mixed with other metals to harden it. Different mixtures lead to different properties especially in terms of color.

A jewel is never 100% pure gold because it would not hold its shape. 18 karat (18k) jewelry is 75% pure gold and 25% other metals. The other metals can be silver, copper or palladium depending on the color one wants to achieve. To learn more about the difference between 24k, 22k, 18k, etc.

Some jewelry stores also mix nickel into their gold alloys especially white gold. I do not use nickel in my jewelry because it causes allergies in many people. And I suggest not buying jewelry with a high level of nickel.

Platinum

Traditionally, platinum is used for jewelry with a lot of diamonds. Here are the main characteristics of platinum:

• Platinum has a natural white shine that highlights the brilliance of diamonds.
• Also platinum is stronger than gold, so it holds stones more securely. Even sometimes a gold jewel will have the stone held together with platinum because of the platinum's durability.
• Platinum is also quite dense, so a platinum jewelery feels heavier.

Generally there are jewelers specialized in working only with platinum. But since platinum is not as fashionable as it used to be, there are fewer and fewer jewelers with the know-how. 

Like gold, platinum is not used in its pure state. A piece of jewelry will generally be 95% pure platinum. The other metals can be copper, cobalt, or a noble metal such as iridium, ruthenium, or palladium.

An interesting feature of platinum is what happens when it is scratched off. For most metals, when scraped, a small bit of the metal falls off. But platinum is very hard, so when you scratch it, the scratched part moves to another part of the piece. Over time, the jewel takes on a slightly gray color that makes it look like an antique. It is one of the charms of this metal.

Palladium

Palladium jewelry can be made but it is quite rare. It is more common to use palladium in what is called "white gold". 

Pure gold is naturally yellow. By mixing pure gold with palladium, the result is a white color. 18k white gold can have an alloy of 75% pure gold with maybe 16% pure palladium and 9% pure silver. 

Rodio

Rhodium has a high shine, so it is used to plate gold, platinum or silver. This bath leaves a thin layer of rhodium, and the piece remains very shiny.

Unfortunately, the rhodium plating is superficial and wears off over time. It is rare to find pure rhodium jewelry because it is a difficult metal to carve. 

Silver

Silver is probably the most ubiquitous noble metal in jewelry. Silver is generally found in three formulations: 950, sterling silver, and 900. The term 950 means that the jewel contains 95% pure silver and 5% other metals such as copper. Sterling silver is synonymous with 925 which is 92.5% pure silver and 7.5% copper. And 900 silver has 90% pure silver and 10% copper.

Freshly and well polished, the silver has a fairly strong shine. Unfortunately, this metal is more reactive compared to the other noble metals. The silver reacts with sulfur in the air, and this causes the silver to lose its shine and change color. But with good care, tarnishing of silver can be avoided.

Summary of the most important base metals in jewelry

Copper

Perhaps the most important base metal in jewelry is copper. Copper is a soft metal like gold and silver. But by mixing copper with these noble metals, the result is a harder metal. This allows the jewel to keep its shape. 

This phenomenon is due to the atomic structures of copper versus silver and gold. The copper atom has a smaller radius, so it ends up getting between the spaces. That creates a harder metal.

Copper also plays a fundamental role in pink and red golds. As already mentioned, pure gold is naturally yellow. By mixing pure gold with copper, the gold takes on a redder color.

There are some people who have an allergy to copper, but this allergy is not very common.

Tungsten

Tungsten is a highly hard metal that does not scratch easily. Actually, the tungsten jewelry on the market is tungsten carbide – a mixture of tungsten with carbon. 

Tungsten carbide is so strong that it is used in industrial drills, drill bits, and hammers. So you can already imagine how durable a tungsten carbide jewelery is. At the same time, its hardness makes it a jewel susceptible to fractures if it receives too strong a blow.

Titanium

Similar to tungsten in terms of color, titanium is a harder metal than gold and silver. The big difference is that titanium is much lighter and less hard compared to tungsten. And titanium doesn't fracture as easily as tungsten. 

Tungsten and titanium are cheaper alternatives to precious metals. It is becoming more and more fashionable to see titanium or tungsten wedding rings for men.

Iron

Iron rusts quickly and is hardly used in its pure form. But today it is common to find cheap stainless steel jewelry. Stainless steel is a combination of iron with chromium and other metals such as nickel, copper or titanium.

Stainless steel is quite popular in inexpensive jewelry especially because it does not corrode. Certain stainless steels contain the metal nickel, which can cause an allergy. But you can find nickel free jewelry too.

Zinc

Zinc is a base metal used primarily to bleach gold. I personally do not use this metal in my jewelry because I prefer to use the noble metal palladium to whiten pure yellow gold.

Nickel

Nickel is a metal that can also be used to bleach gold. But this metal causes skin allergies in many people, so all my jewelry is nickel free. In fact, the European Union has certain restrictions against the use of nickel in jewelry. 

There is a metal called "alpaca" that has a certain similarity to silver. But "alpaca" is made of nickel, zinc, and copper: three base metals with no precious metals at all. Alpaca can cause allergies due to its high level of nickel.

Source: edgartica