This blog explains the process of metal plating, why jewelers and manufacturers use it, and some general information to help you make informed decisions on purchasing and production.
Plating in the jewelry industry is a common practice and used for many different reasons. It can be applied in a large manufacturing setting or in a small studio. In this blog we’ll explain how the plating process works and some of the challenges associated with it. We’ll also discuss why items are plated and clarify why plating is used on gold-filled products in particular. We’ll break it all down so you can make informed decisions on purchasing, understand discrepancies in plated products, and decide if plating is something you’d like to introduce into your jewelry line.
What is jewelry plating and how does it work?
Electroplating is the process of using an electric current to deposit a layer of metal onto a conductive item. It is the most common form of plating in the jewelry industry. An example of jewelry electroplating would be adding a thin layer of gold to the surface of a metal chain necklace.
How exactly does this work?
- The rack of jewelry is submerged in a tub full of a chemical solution containing suspended metal particles.
- The electrolyte solution receives a positive charge.
Depending on what material and color you’d like to plate with, the chemical solution you use will be different. The recipes, so to speak, can also be different from one plater to the next. Silver plating uses a pure deposit of fine silver. Gold plating is most likely an alloy, like 14k or 18k, and therefore there is much more variation possible in the recipe.
Challenges with Jewelry Plating
Plating is often done by specialists because it can be a tricky process. Companies that only do plating have very large baths where the plating takes place. At home you may have a small bath, like a beaker. Larger baths are more stable and less prone to contamination. Any material that’s not supposed to be in your plating solution can cause issues. A small amount is going to affect a beaker at a greater scale than a multi-gallon bath. Every time you plate, especially with gold, some material in the solution is plated out, meaning it’s deposited onto the pieces and therefore changes the bath ratio. Using a depleted solution can affect the final color on later batches. Plating specialists frequently analyze their baths to ensure the most consistent results possible. Analysis happens in-house or samples are sent to specialized labs. Regular solution analysis is a challenge for a small jeweler.
Additionally, the chemicals used in plating are harsh and require special handling. Although you can purchase them at small quantities, you should know the hazards. For example, cyanide is common in plating solutions. Be aware of exposure risks and recommended protection measures since cyanide is toxic. The use of plating chemicals also requires proper storage and disposal. You cannot just dump solutions down the drain. Talk to your local waste disposal organization prior to purchasing to understand the regulations in your state and city. Be sure to review the SDS, or safety data sheets, to understand exposure risks and protect yourself. Your plating solutions supplier should have SDS documentation available for you to review. Watch our Jewelry Studio Safety webinar for general tips and more information on SDS sheets.
Plating and Surface
The surface of the jewelry can affect the appearance of the plated material. A matte finished piece will look duller after plating than a piece that has been pre-polished. The size and uniformity of the surface area also matter – items that are larger or smaller may appear to be a different color despite being plated in the same material. Our brains can play tricks on us due to variations in surface area size and texture. These factors impact the reflection of light and how our eyes perceive color. The examples below show how different the same gold plating finishes can look on items with different textures or continuous surface areas.
|
|
|
|
Additionally, plating cannot fill scratches on your jewelry either. In many cases, the plating will actually enhance the visual appearance of scratches. What it can do though, is improve color uniformity and hide any discoloration that occurs during manufacturing or making. If you are considering plating any of your jewelry pieces, make sure they are finished to a quality you are satisfied with and would sell – plating is often the last step of the production process.
Why plate jewelry items?
Plating is commonly used on costume jewelry to make cheap materials look like fine jewelry made of precious metal. But plating is also used as a finishing technique for gold and silver items. You may be wondering why anyone would plate precious metal jewelry items if they’re already genuine materials. You will often encounter jewelry chains from your favorite suppliers, like Halstead, that are silver or gold, and also plated for finishing. This is done for a few reasons.
Manufacturing happens at a vastly different scale than making work at the bench. Items are made at a different speed and size of production run. You might make three pairs of earrings at once, but a jewelry manufacturer may make 3,000 pairs at once. Because of this, certain processes done by hand just aren’t effective anymore – like polishing.
Manufactured items are often plated instead of polished. Plating is more cost effective and faster than polishing. It will get into all the nooks, crannies, and crevices of a jewelry piece that can be difficult to polish. A bright, shiny finish is also in style right now and preferred by customers. Plating is the most efficient way to achieve the desired results at scale.
Plating is commonly used to cover solder seams that will tarnish faster than the rest of the piece. Most chain links are soldered closed, and plating is a great option to cover solder joints. The plating creates a uniform surface color too. Depending on the plating material, it can resist natural tarnish reactions. Sterling silver is often plated with a surface layer of fine silver because it tarnishes more slowly. Or, you may also see sterling silver that is rhodium plated. Rhodium plating is a darker gray color than sterling or fine silver, but it’s incredibly durable and helps prolong tarnish-resistance.
Plating isn't always just a technical decision. It can be an aesthetic choice too. Different plating colors are deliberately used for aesthetic reasons. A jewelry designer may use plating simply to enhance colors or provide different visual effects. Sterling silver jewelry and findings are often plated with .999 fine silver to get a brighter, white metallic shine that is preferred by modern consumers. In the past, tastes and preferences leaned towards the darker grey color of un-plated .925 sterling material. However, different manufacturers sometimes choose other plating colors that suit their brands. Some large jewelry companies even have ‘signature’ blends to provide identifiable uniformity across their collections. Consumer demand plays a role in plating options too. For example, some customers want the look of gold at an affordable price. But they may not want to buy imitation costume jewelry So, jewelers offer gold-plated sterling silver to provide a fashion option that is still made entirely of precious metals.
Jewelry Plating Limitations
Plating deposits a very thin layer of material. It can wear off over time with extended wear and expose the material underneath. This is especially true for jewelry items that are worn every day. Rings are likely to wear more quickly between your fingers where there is constant friction. Jewelry that you frequently leave on in the shower, while swimming, and overnight will wear more quickly too.
Sterling silver jewelry will eventually tarnish no matter how you finish it, even if it is plated with fine silver or rhodium. These plating finishes can delay tarnish, sometimes for many years, but they cannot stop it forever.
Silver and Gold Plating Color Variances
Getting the color just right on plated items is a process with many variables. When thinking about plating, it’s best to think about it like painting a room in your house. If you’re painting over a beige wall and a dark blue wall with the same white paint, the outcomes will look very different after one coat of paint. Plating is very much the same. The color of the material underneath will affect the final color. A thicker plate will create a more even color. However, especially with gold plating, that will raise the cost significantly. Manufacturers must balance the cost with the color.
Common chemicals found in household goods can have a substantial affect on plating color. Even small amounts of contaminants on surfaces, in the baths, or on workers' gloves can impact results, causing color shifts. Professional platers never handle metal without clean gloves before it goes into the bath to prevent any lotions or perfumes from getting on the metal. Jewelry and tools must be clean too.
Plating and Gold-Filled
Gold-filled is another precious metal option for consumers. As you may already know, gold-filled is a layered material. It’s a layer of karat gold alloy, usually 14k, bonded to a core of jewelers brass. Read up on gold-filled details in our dedicated Gold-Filled Resource Area. Gold-filled material has a thicker layer of gold than gold-plating so it is more durable. However, gold-plating is often added over the gold-filled material during finishing for the technical and aesthetic reasons already described.
Decades ago, when gold-filled was introduced, the fashion preference was for an 18k gold color called ‘Hamilton finish.’ It is a tawnier yellow color compared to the muted shine of 14k that we see most often today in the United States jewelry market. However, in other countries, Hamilton finish is still preferred. Many gold-filled jewelry manufacturers that sell internationally are inclined to use a Hamilton finish. It has broad international appeal and it is the more "traditional" gold-filled color. Trends are changing though, and the United States market is important for manufacturers. Some companies are now choosing raw or 14k plated gold-filled finishes instead. That’s why you may order chain, jump rings, and blanks in gold-filled and notice color variations. Each company may have a slightly different recipe for their plating solutions plus they may choose to use the Hamilton or raw 14k finish colors.
Since Gold-filled is a layered material, it can be difficult to work with and cannot be cast. No files or abrasives should be used on gold-fill because it can remove the entire gold layer, revealing the brass below. It can be soldered, but with extreme care and expertise, as excess heat is likely to melt the layers together. Most volume manufacturers use high-end laser welders to minimize surface damage to the material during soldering. If a gold-filled item has significant solder joints, you must plate it. Brass and gold will not tarnish or wear in the same way. Any exposed brass near a solder joint will tarnish black more quickly. Once this happens, tarnish can bleed through from the brass core underneath to the gold alloy surface layer. It cannot be removed. Because of this, plating is often used in the manufacturing process of gold-filled jewelry and supplies to protect the solder joints from tarnish reactions.
Gold-Filled Popularity
Gold-filled has become more popular over the past few years. There is much more demand for jewelry supplies that used to only be available in sterling silver or solid gold. As the demand grew for a wider variety of gold-filled products, plating over solder seams became necessary. Solder seams will always be a different color than the gold-filled because the solder is a different alloy, or composition of metals. Manufacturers will plate soldered jewelry items for consistency in the final product. With growth in popularity also came an increase in manufacturers producing gold-filled products. This, in turn, adds to the color variations explained above because they may use different plating colors and solutions.
Plating in your Jewelry Studio
Much of this article addresses plating at a larger scale, but you can plate items in your own studio too. You can buy plating kits and rectifiers for small-scale electroplating from suppliers like Gesswein and Pepe Tools. It is important to remember that this process should not be done without proper ventilation and the ability to store and dispose of harsh and toxic chemicals.
An easier introduction into plating in your own studio is pen plating. This allows you to paint the plating solution onto your piece and add plating exactly where you want it. It’s great for creating a mixed-metal look. Pen plating is a solution for smaller areas that you want plated. It is not conducive to plating entire pieces that are larger.
It's easy to see which gold-filled items are gold-plated in finishing for your favorite Halstead products. Scroll down on the product detail page to the 'Specs' section. Under the Finish disclosure you'll see 'gold-plated' for items that are gold-filled with gold-plating too. You'll see 'bright finish' for items that are raw gold-filled with no plating.
Check out more information below:
