Metals can be elements or alloys. Elements are the basic building blocks of chemistry. Examples of elements: Oxygen, nitrogen, hydrogen, iron (Fe), copper (Cu) and niobium (Nb).
Lead (Pb) is an element that was traditionally popular as an ingredient in casting alloys (and some other alloys) because it makes some metals softer, less brittle and/or helps them melt at lower temperatures. Lead is now known to be related to certain health problems (especially in children), and many governments are regulating allowable amounts of lead in jewelry components. Jewelry components containing lead are generally considered safe for adults to handle and wear externally, as adults are less likely to ingest their jewelry. More about lead in jewelry components.
Alloys are mixtures of various elements. Alloys can be a "base" (less costly) metal, like brass, or a "precious" (more costly) metal, like sterling silver or karat gold. Jewelers and engineers create alloys to change the color, melting temperature, and/or strength of elements. For example, solid gold is too soft for most applications. To make it stronger, it is alloyed (mixed) with other elements.
What are Base Metals?
Base metal is a catch-all term in the jewelry industry for metals used in costume jewelry. In metal working, base metal is any metal that is not one of the noble or precious metals. In costume jewelry, base metals are often plated with a very thin layer of gold, silver, nickel, rhodium or other metal on the surface of the bead, finding, chain or other component.
Common base metals include:
Brass is an alloy of copper, zinc and sometimes other metals. It is typically 70% copper and 30% zinc. Our red brass wire is 90% copper, and 10% zinc, which gives it a slightly warmer color. Raw (unplated) brass components are usually the same color as yellow (plated) findings, although they will vary in color and may also work with gold plate. Their surfaces may be imperfect and their finish may change with age.
Copper is an element that's bright reddish-orange in color. Over time, it will darken and gain a patina, sometimes with a greenish hue. Copper can also discolor skin, most commonly when it is worn snugly like a finger ring or tight-fitting bracelet. Copper is a soft metal, which makes it great for wire wrapping. Because of copper's softness, solid copper components are less durable than copper-plated beads and findings.
Nickel silver is sometimes also called German silver. It is a base-metal alloy of nickel, copper and zinc. While nickel is silver in color, it does not contain any sterling silver. Our nickel silver wire is 65% copper, 18% nickel, and 17% zinc. The relatively inexpensive cost of nickel silver compared with sterling makes it an attractive option for jewelry components. Just be aware that some people are allergic to nickel.
Niobium is highly resistant to corrosion and other reactions, and is used in medical implants. Niobium jewelry findings come in several anodized colors. Anodizing is a way to color metal by dipping it into an electrically charged "bath" that creates bright colors without plating or painting the surface. The colors don't flake or chip like plated or painted surfaces can. The main drawback of anodized niobium is that it doesn't match basic silver and gold colors. On the upside, niobium is an inert element, with no nickel, lead, or other additives, most people with metal allergies can safely wear niobium.
Pewter includes any of the numerous silver-gray alloys of tin with various amounts of antimony and copper.
TierraCast products are made with a lead-free pewter called Britannia pewter, which consists of tin, antimony, and copper. Most TierraCast Britannia pewter beads and jewelry findings have a surface finish (
plating) of a different color over the pewter base. Other base-metal items marked "antiqued pewter" may be brass or zinc with an antiqued pewter plating. In nearly all cases, these zinc or brass alloys meet
Steel is a blanket term for a wide variety of iron-based alloys that are very tough and hard.
Cold-rolled steel is shaped when the metal is below its recrystallization temperature (usually room temperature). The metal is literally pressed between rollers in a mill to flatten and thin the steel. This cold processing method work hardens the metal and strengthens it up to 20% more than hot processing. It also creates a very smooth surface with a uniform finish. It allows for the creation of small products with great strength.
AFNOR XC45 steel is a specific type of cold-rolled steel, and is a combination of XC45 and XC75 (AFNOR) steel — also known as 1045 steel and AISI 1078 steel, respectively. The alloy is a carbon steel with no nickel added, meaning it meets the strict standard of the
EU Nickel Directive. Jewelry findings made of AFNOR XC45 steel include superior-quality French barrette backs and shoe clips.
Stainless steel (a.k.a. corrosion-resistant steel) is a generic name for any steel alloy with a minimum of 11.5 wt% chromium. Common types or grades include 440, 304L, 316L and 904A. In all types of stainless steel, the chromium creates a very thin chromium-oxide layer on the surface of the metal which prevents it from rusting.
The advantage of stainless steels over plated steels is that, if scratched or damaged, the stainless steel 'self-repairs' as a new chromium-oxide layer is formed. In plated steels, scratches in the plating can lead to corrosion of the steel underneath. In general, the higher percentage of chromium, the stronger the corrosion resistance of the steel. Other metals are added to the alloy to give the steel other properties, such as strength and malleability. Nickel is added to strengthen the protective oxide layer.
Stainless steel findings are slightly more gray than white findings, but the difference is barely noticeable, especially on finished jewelry. Stainless steels do not match sterling or silver plate well.
304 stainless steel is the most popular grade of stainless steel. It is 18-20% chromium, 8-10.5% nickel, 0.08% carbon, plus iron and the trace elements listed above. It is commonly used in the food industry (sinks, coffee urns, dairy storage and hauling, beer/brewing, citrus and fruit juice handling, etc). The same corrosion and stain resistance that make it great for food handling, also make it popular for jewelry.
304L stainless steel is almost the same as 304, but has a lower carbon content (0.03%), and may contain a slightly higher amount of nickel (8-12%). This alloy has increased weldability and resistance to corrosion (great for men's jewelry).
430 stainless steel contains less than 0.75% nickel, and some forms of 430 stainless steel meet the EU nickel directive (less than .05% nickel ion migration). 430 stainless steel has good corrosion resistance compared to non-stainless steel, but not as good as the 304 and 316 alloys. This makes it less popular for jewelry than you would expect from its low nickel content. However, it is gaining in popularity due to the low nickel content, and we now have bead caps in addition to earring findings in 430 stainless steel.
Surgical stainless steel is a specific type of stainless steel which, while wearable by the majority of the population, does contain a small amount of nickel (to which some people are
allergic), usually 8% in jewelry.
316 and 316L surgical stainless steel contain 2-3% molybdenum for even greater resistance to harsh corrosives (both industrial, and in the body). 316L is a low carbon version of 316, with extra corrosion resistance, and is frequently used for stainless steel watches and marine applications. Like most other stainless steel, it contains 8-10.5% nickel, making it unsuitable for people with nickel allergies.
Titanium is a very strong metal that's resistant to corrosion. Because of this, it's frequently used in medical implants, and it's an excellent choice for people with nickel allergies. Our
titanium ear wires and earring posts are Grade 1 ASTM F67, which is unalloyed commercially pure titanium, and meets the
EU Nickel Directive. Our
titanium earring posts have either a Brittania pewter pad, or a stainless steel 430 flat pad.
"White metal" and "pot metal" are terms for tin-based alloys used in low temperature casting of base-metal jewelry components. White metal is the "silver" color that you most often see on costume jewelry and base-metal findings. White metal castings are usually three-dimensional rather than flat and are often plated. The exact composition of white metal varies, because each casting foundry and shop uses its own proprietary formula.
See platings for more information on colors of base-metal components.
What are Precious Metals?
The term precious metal refers to rare metals of high economic value. The term usually includes platinum, gold, and silver. A metal can be considered a "noble" metal (meaning it is highly resistant to corrosion) without being a "precious" metal. Gold, silver, and platinum are generally considered to be both noble metals and precious metals. Some years, market "spot" prices of precious metals fluctuate greatly. An immediate effect will be noticed in sterling, gold filled and 14kt gold wire, sheet, beads and findings. If prices remain particularly high (or low), there will be a similar (but smaller) effect in the prices of silver-plated and gold-plated (base metal) items.
Precious metals at Rings & Things include:
Sterling silver, sometimes stamped .925, is an alloy of at least 92.5% silver,
and (usually) copper. It is a soft, easy to work with metal, which can be antiqued to a dark black or polished to a bright shine. More information about sterling silver.
Argentium® sterling silver is a tarnish-resistant variety of sterling that consists of 1.2% germanium, 6.3% copper and 92.5% silver. For the end user, Argentium's main attraction is its tarnish-resistance which requires much less maintenance than traditional sterling silvers. For metal workers, Argentium offers additional benefits. It does not develop firescale, which both saves artisans time and makes it environmentally friendlier than traditional sterling. Argentium can be made nearly twice as hard as standard annealed sterling silver by a simple heat treatment, and it is laser weldable. These properties allow for expanded design possibilities.
Fine silver, sometimes stamped .999, is at least 99.9% pure silver, which means it is softer and more malleable than sterling. It also tends to take longer to tarnish. Fine silver findings and wire are compatible with Art Clay™ Silver and Precious Metal Clay.
Silver fill is made by using heat and pressure to apply a layer of .925 sterling or .999 fine silver to a base of less costly metal. This produces a surface of sterling silver or fine silver that is hundreds of times thicker than a silver plating. There are no industry standards yet for silver fill, but the
silver-filled components Rings & Things carries are at least 1/20th silver by weight.
Karat (kt) gold: Pure gold is 24kt, meaning 24 out of 24 parts are gold. 24kt is too soft to be functional, so it is alloyed with other metals for durability, cost and color. 14kt is 14 parts gold out of 24, and the remaining 10 parts are other metals. Depending on the color of gold (which can be yellow, rose, green or white), the other parts may be copper, silver, nickel, zinc, tin, palladium and/or manganese. People with nickel allergies should be aware that, until recently, most white gold contained nickel. Today, palladium is used to make a white gold alloy that is less likely to react to the wearer's skin.
Gold fill (also called gold overlay) is made by using heat and pressure to apply a layer of karat gold to a base of less costly metal. This produces a surface with karat gold. The minimum layer of karat gold must equal at least 1/20 of the total weight of the item. Gold-filled beads, wire, and jewelry findings we carry.
Gold-filled tubing and wire are usually seamless, so only gold touches the body. Gold-filled sheets of base metal, used to make other findings, can be either single clad (gold on visible side only) or double clad (gold on both sides and sometimes the edge). Seamless and double clad gold-filled items are less likely to discolor, since the base metal is sealed inside the gold. However, the layer of gold on a single clad 1/20 gold-filled item is as thick (and the same total weight) as the two layers of gold on a double clad 1/20 gold-filled item. Use care when buffing gold-filled items, to avoid removing the gold layer.
The surface layer of karat gold on gold-filled items is usually 10kt, 12kt or 14kt (see illustration for more info). To know the thickness of the layer, look for a fraction, such as 1/10 or 1/20. It will be 1/20 unless otherwise stamped. Examples:
1/10 10kt GF: 1/10 of the total weight must be 10kt gold.
1/20 12kt GF: 1/20 of the total weight must be 12kt gold.
What are Ethical & Green Metals?
The terms "ethical metals" and "green metals" describe metals made from previously used materials that are refined and reused, as opposed to metals that have been newly mined. Some silver and gold have always been reclaimed (recycled) from scrap jewelry, electronics, industrial scrap, photo processing, and other sources. In this sense, precious metals have always been green.
Rings & Things asked our suppliers of silver sheet and wire if their materials are made from newly mined or recycled materials. All of them responded that they use recycled silver. Once a product is cast, stamped, or milled, there's no way to tell where the metal came from. This means that we must rely on what manufacturers tell us. Nevertheless, the historical precedent of recycling precious metals, combined with high prices in metal markets, means it's safe to assume that at least some of our
precious metal beads and
jewelry findings are also made with so-called ethical metals.
What are Platings?
A plating is a thin deposit of metal that is electro-chemically or otherwise applied to the surface of a different metal base. Other materials, like plastic, can also be plated. Many plated items are plated with copper first, then the final color.
Terms like white, yellow, silver plate, and gold plate can be somewhat ambiguous when you're trying to determine whether or not the
clasps in your hand will match the
ear wires, etc. listed in a catalog. Here are our plating definitions, which are fairly standard throughout the jewelry industry:
White plate is the "silver" color most often see on costume jewelry and base-metal findings. White-plated components are generally grayer, but also more durable, than silver-plated components. They generally do not tarnish. The plating is typically an imitation rhodium made of copper, tin, zinc, and/or nickel.
Many white-plated TierraCast® components have a plating of real rhodium over a nickel undercoating. This nickel undercoating may leach, making rhodium-plated Tierracast supplies non-compliant with the
EU Nickel Directive. Rhodium is brighter and more silvery than other white platings, but still more gray than actual silver.
Silver plate is a thin surface layer of actual silver. It nicely matches the color of sterling silver; it doesn't quite match our white findings. Like sterling silver, silver plate can tarnish. For this reason, it's frequently lacquered to prevent tarnish (until the lacquer wears off).
Antiqued silver plate is a thin surface layer of silver that has been darkened to provide a "distressed" (oxidized) appearance.
Antiqued pewter plate is a pewter-colored plating that has been darkened to provide a "distressed" (oxidized) appearance. Some antiqued pewter beads and findings are matte, while others are shiny.
Yellow plate is a gold-colored plating that is slightly brassier than gold plate, and is sometimes longer lasting. Yellow finishes go best with raw brass.
Gold plate is a very thin deposit of actual gold (about 1/1,000 - 1/1,000,000 of an inch). The color matches 14kt gold. Heavy gold electroplate might be 2 or 3/1000s of an inch thick (this can also be written as 2 or 3 mils). Learn the difference between gold plate and gold fill. Many gold-plated items have a white nickel plate under the final gold plate. Warning: hand lotion will accelerate tarnish on gold plated components, and can result in a black color within days of handling.
Gilt is a very thin finish of gold color that is not actual gold.
Vermeil, pronounced "vehr-MAY," is a plating of karat gold over sterling silver (see Precious Metals for more info).
Antiqued gold plate is a very thin surface layer of actual gold (about 1/1,000 - 1/1,000,000 of an inch) that has been darkened to provide a "distressed" (oxidized) appearance. Warning: hand lotion will accelerate tarnish on gold plated components, and can result in a black color within days of handling.
Antiqued brass components typically have a brass or zinc base with a brass plating. The crevices of antiqued brass beads, charms and findings are darkened to give them a "distressed" (oxidized) appearance.
Copper plate is a bright, shiny copper plating. Because the metal underneath the plating is usually a harder metal than copper, copper-plated components tend to be more durable (less bendable) than solid copper parts.
Antiqued copper plate is a copper plating that has been darkened to provide a "distressed" (oxidized) appearance.
An allergic reaction to nickel is one of the most common metal allergies that you or your jewelry customers may experience. People with slight nickel allergies can usually wear surgical stainless steel for a few hours, or possibly all day. But some people are so sensitive that they cannot even wear watches, or have the buttons on their Levi's touch their skin. For nickel-allergic people, we suggest
sterling silver earring findings,
titanium earring findings, and
nonmetal earring findings.
"Nickel free" can be a confusing term since items marked nickel free are allowed to contain a tiny, but still measurable, amount of nickel (huh? read on...). There is not yet a US standard for the amount of nickel allowed in jewelry components. The European Union's standard, typically called the EU Nickel Directive, limits the amount of nickel that may be released onto the skin from jewelry and other products. These "migration limits" are different from measuring the percentage of nickel that exists in an alloy's composition. The UK has adopted the EU Nickel Directive as its nickel standard. If you have customers in the UK or EU – or if you want to start marketing your jewelry in those countries – you'll want to comply with the EU Nickel Directive. More nickel-free & Nickel Directive info.
Hypoallergenic is a popular marketing term, but has no legal definition. When your customers request hypoallergenic jewelry, we sugggest you direct them to nickel-free options instead. For more about the term "hypoallergenic" and a variety of excellent options to minimize allergic reactions, see our
blog post "Surgical Stainless Steel and Hypoallergenic Metals". One thing that makes this more complicated is that metal allergies are just like food and other allergies -- not everyone is allergic to the same thing.
Patinas & Oxidizers
A patina is a corrosion or oxidation that takes place on a metal surface. Rust on iron is one example; tarnish on silver is another. Patinas often form naturally by long exposure, but can also be created artificially for an antiqued (a.k.a. distessed) look.
Antiquing solutions (a.k.a. oxidizers) are frequently used by jewelry makers to add a patina to metal beads, charms and findings. Rings & Things carries solutions that give a deep black patina or a brown-black patina. Each can be used on a variety of metals. Before using an antiquing solution, be sure to read the directions and safety precautions, and follow them carefully!
If you like to experiment with your own patinas and decorative metal finishes, we recommend these books: