Sunday, January 18, 2015
Gold-filled is constructed in two or three layers. The core metal is jewelers’ brass. Single clad gold-filled has all the gold content in a single layer on one side. Double clad gold-filled splits the gold content into surface layers on both sides of the material. The gold alloy is then bonded to one or both surfaces of the brass core with heat and pressure. The bonded raw material is then sold as sheet or wire to jewelry manufacturers for use in designs.
Gold-filled is legally required to contain 5% or 1/20 gold by weight. This 5% is then described by the karatage of the gold alloy. Most gold-filled is 12kt or 14kt gold-filled. It is most accurately labeled with the karatage, the “/” symbol, and then 20 to reflect this construction. Products are identified as 14/20 Gold-filled or 12/20 Gold-Filled; alternatively, 14kt Gold-Filled or 12kt Gold-Filled are also acceptable.
Gold-filled cannot be cast. This is a major limitation in the types of products that can be manufactured in gold-filled. Products must be made from sheet, tube or wire that retain the layers constructed in brass and gold. Casting by definition is melting the metal material which would alloy the layers into one big melted mess.
OK, this one isn't a question but it raises an important issue. Some jewelry designers will refer to gold-filled items as just “gold.” It is not gold and it is illegal to call gold-filled items gold, which implies they are a solid alloy with much higher pure gold content. Gold-filled is a unique material and must be clearly distinguished from solid gold by professionals in the industry. “Gold” is not an acceptable short hand and it can get you in legal trouble for fraud.
No, gold plating is a miniscule layer of solid gold applied to a brass base. The plating does not compose any measurable proportion of the product’s total weight. It is estimated to be 0.05% or less of the metal product. Gold plating will wear off rather quickly and expose the brass base product. It does not stand up to heat, water or wear over time. By comparison, gold-filled contains 5% gold by weight; moreover, all the gold is on the surface which offers product protection from tarnish and wear.
Yes it can, but it takes a rare set of circumstances. Gold-filled is usually a lifetime product because the gold layer bonded to the brass core is quite thick. However, in rare instances of extreme sulfide exposure the gold-filled can blacken. This has only occurred a handful of times over our decades of gold-filled use. Foreign transit through extremely polluted shipping docks in a few countries has caused the product to blacken on several occasions. The only domestic cases we have had were products stored in nail salons with high levels of chemical sulfide fumes and due to a fire where the structure was filled with smoke and all the gold-filled in the building turned black. These are extreme conditions that are unlikely to happen to most end users. However, it has made me think twice about breathing the air in nail salons. Usually, gold filled just requires light surface cleaning with an untreated cloth or mild soapy water.
Gold-filled is a reasonably priced, quality alternative to solid gold. Most gold-filled items are made in the USA.
9 Types of Silver Used in Jewelry
There are many types of silver available on the market today. It is important to be familiar with the competing metals in the marketplace in order to educate your customers about silver quality standards and alternatives in the industry. Below you will find definitions and comparisons of the many silver metals used to make jewelry around the world.First, customers need to understand that silver used in jewelry is usually an alloy which means a metal mixture of two or more elements from the periodic table. Silver is an element. Other metallic elements may be alloyed with silver for various reasons that will be described below.
Second, a lot of finished silver jewelry will have a quality stamp somewhere on the piece. This is the quickest way to identify quality. There are cases of fraudulent marking but they are fairly rare. These tiny markings may only be legible under magnification. However, jewelry items or components are only required to bear a stamp when there is sufficient surface area available. For that reason, many small findings and components are unstamped even though they are quality alloys. Quality stamp standards are described below when relevant.
1. Fine .999 Silver
Fine silver is the closest metal to the pure element silver. It is described as .999 which indicates 99.9% purity. The 0.1% remainder consists of trace elements of insignificant quantity. Fine silver has a more vitreous luster than the bright polish of sterling. It appears more gray and slightly dull. Fine silver is quite soft and will scratch, dent and change shape fairly easily. For that reason it is less common in jewelry because items will not wear well over time. However, there are benefits to fine silver. It is easy to form, it fuses without solder and it is highly resistant to tarnish. Because it is a soft metal it is best used for earrings or necklaces instead of rings or bracelets that are bumped and scratched more frequently. Silver clay products reduce to fine silver and have increased the demand for pure silver jewelry in the US market. Hill Tribe silver is often .999 as well. The most common quality stamp on this metal is .999 FS or just .999.
2. Sterling .925 Silver
Sterling is the jewelry quality standard in the United States and most world markets. It is an alloy of 92.5% silver. The remaining 7.5% is usually copper though it is sometimes other metals such as nickel. The other metals are added to the alloy to increase hardness so the metal will be more durable and to create the color and luster that is so prized by consumers. Sterling silver is the silver color we are most familiar with. It is very bright and shiny but it will tarnish. Tarnish can be delayed but it cannot be prevented and it is easy to clean with readily available polishing products. Sterling silver is harder than fine silver but it is still fairly soft compared to many metals. Fine chain and thin metals can be stretched or “drawn” under tension. And jewelry can be scratched or dented if it is banged around. Sterling can be soldered, formed and annealed repeatedly. The most common quality stamps are .925 and Stg.
3. Argentium Silver and Non-Tarnish Alloys
Non-tarnish alloys are fairly new to the market. Argentium is one brand but there are others available that are quite similar. These alloys are a minimum of 92.5% silver though some will be slightly higher in silver content. The remainder consists of copper and the addition of the element germanium. The germanium makes the alloy harder and resistant to tarnish. Non-tarnish alloys can still tarnish under extreme conditions and after extended periods of time. But, they will generally require less maintenance than sterling. This tarnish resistance is the chief benefit of the metal though it is also notable that Argentium will also fuse without solder. The trade-off is price. Argentium is significantly more expensive than sterling and less readily available. It is also difficult to distinguish from sterling once on the market because the quality stamp is still .925. Manufacturers can go through an application process to receive authorization to use the Argentium® mark as well but this stamp is large and impractical for many jewelry pieces.
4. Coin Silver
Coin silver was once a more common alloy in the United States. It is now fairly rare and the name causes quite a bit of confusion. The technical “coin silver” alloy is .900 silver, or 90% silver and 10% copper. It was not used to make coins; rather, it was so named because it was made from refined scrap coins at one point in time. Monetary coins in our country, and most others, no longer contain silver and are instead made from more inexpensive, durable base metals. There are some collectible coins or coin investment instruments with higher silver content but those will be marked as such and usually come with certificates of authenticity. Coin silver jewelry that is still on the market will bear a quality stamp of .900. Many of these pieces are antiques.
Jewelry sold as just “silver” is a bit of a mystery. The term is thrown around in the market but jewelry items should be clearly identified as a specific standard quality. If not, it is unlikely that the silver alloy is very high quality. Jewelry artists and manufacturers are legally required to either stamp pieces when space permits or tag finished products with quality designations.
Silver-filled is a new layered metal that was introduced during the recent surge of silver prices during the recession. It is not an alloy because the metal content is not the same throughout the material. Instead, the sterling silver is all on the surface. Silver filled is either 5% or 10% sterling silver by weight fused with heat and pressure to a brass core. This metal is fairly new so it is not standardized in the US. Since silver-filled is a layered metal it cannot be cast. The silver layer is much thicker than silver plate but this is still a much lower quality product than most solid silver alloys. It will tarnish and it should only be soldered with precision equipment and special training. Now that the price of silver has come down from past highs the metal is less common in the market. There is no legally approved quality stamp standard for silver-filled at this time.
7. Silver Plated
This is a base metal product with an extremely thin plating layer of silver applied to the surface. Even when jewelry is described as fine silver-plated, the overall silver content is a tiny fraction of a percent. Silver-plated jewelry is affordable costume jewelry. Plating can tarnish and will eventually wear off to expose the base metal underneath. Costume jewelry will not have a quality stamp but it may bear the manufacturers logo or hallmark.
8. Nickel Silver
Nickel silver is a bit of a misnomer because “silver” describes the color of the metal and not the content. This is a base metal alloy consisting of primarily copper with nickel and/or zinc. It is an inexpensive base metal that is similar in appearance to sterling but, again, it contains no real silver at all. It is quite soft and makes an excellent practice metal. It can be soldered but it is sometimes difficult to make solder seams that are not obvious. Nickel silver has many other names on the market such as Alpaca silver or German silver. It is used in costume jewelry but should be clearly described as a nickel alloy since many people are allergic to nickel. We also recommend selling nickel silver as a “base metal” because the term “nickel silver” can be misleading for consumers.
9. Bali, Thai or Mexican Silver
There is a great deal of quality silver coming out of Bali, Thailand and Mexico; however, that silver should also be marked and identified with a quality stamp and/or quality disclosure. There are also much lower grade silver alloys from these nations that are described with just the nation of origin. The name of the source country is no guarantee of quality or silver content on its own.
How do you test for silver quality?
There are two commonly used tests to determine the silver content in an alloy. X- ray testing is non-destructive but requires special, expensive equipment. Jewelry must be sent to a lab for x-ray testing. This test is fairly accurate on most silver items. However, it can be fooled by layered metals and some types of plating so accuracy is less reliable. The best means of testing is called assay, which is a destructive test that melts down .5 grams of metal or more so the alloyed elements and ratios can be accurately determined. This test is extremely accurate when conducted by trained personnel in a reputable lab. Neither of these tests is a viable option for consumers looking for a quick test at home. Instead, consumers are advised to buy silver from reputable sources that are honestly disclosing details on their materials. Quality stamps are also an excellent indicator when available.
Handmade jewelry is crafted by hands, instead of mechanically made with machines. Handmade jewelers use old metal-smith skills, simple tools, and a broad variety of techniques to create their desired forms and shapes. In handmade jewelry you can often observe each item's uniqueness, its dissimilarity from similar pieces. You can also usually sense the cultural individuality, meaning, and even history behind many such designs, even if such information is not provided along with the jewelry. Handmade jewelry techniques require considerable concentration, time, skill, creativity, and dedication. This is often clearly recognizable in the finished piece, making fine handmade jewelry stand out from mass-manufactured, uniform items.