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Since ancient times, gold has been the metal most prized for jewelry. Soft yet durable, it can be shaped, etched, and rolled out into sheets just microns thick. It can be melted down and reused over and over again. Best of all, it never leaves black or green marks on your skin! Because it has been so highly prized, the price of gold has remained high throughout the millennia.
Pure gold is too soft to withstand regular wear, so early metallurgists learned to add other metals to gold to make it stronger. These metal alloys have included copper, silver, zinc, and nickel. In addition to making the gold stronger, these materials can also be used to change the color of gold. If copper is the controlling alloy, the gold is yellow or red. If the controlling alloy is nickel, the gold is white. An alloy of silver and zinc creates green gold. In addition to adding strength and altering color, these alloys make gold less expensive. Pure gold is called 24 karat. Other karat designations (10, 12, 14, 18) indicate the amount of alloy which has been added to the gold. For example, 14K gold is 14 parts pure gold by weight and 10 parts other metals.
Even in these lesser concentrations, karat gold is expensive. The 1742 discovery that silver could be fused to copper to create what became known as “Sheffield plate” set metalsmiths on a quest to develop a process for doing the same thing with gold. In 1817 an Englishman named John Turner discovered a technique for applying a thin layer of karat gold over base metal. He patented his discovery and entitled it: “Certain improvements in the plating of copper or brass, or a mixture of copper and brass, with pure or standard gold or gold mixed with a greater portion of alloy, and the preparation of the same for rolling into sheets.”
During the Victorian era larger pieces of jewelry were frequently made using this “rolled gold” technology, but standards regarding the quality and thickness of this plating did not yet exist. This lack of standards led to considerable variation in durability and appearance. The terminology used to describe this technique also varied. The rolled gold Victorian era brooch shown in Figure 2 is marked “GILT.” Rolled gold jewelry became less popular during the Edwardian era as fashions changed and jewelry became smaller and lighter. Delicate filigree became common. This type of jewelry was fairly affordable for the middle class without the use of plating. The economic boom times of the 1920s, combined with the demand for white metals such as platinum and silver, decreased the popularity of rolled gold even further. During the mid to late 1930s, however, a combination of social forces, economic hardship, government regulation, and changing fashions created a huge increase in the production of what had come to be called “gold filled” jewelry.
Price became an important factor for those buying jewelry during the Great Depression. Disposable income largely disappeared, and although women still wanted to adorn themselves they simply couldn’t afford the precious metal jewelry that had been popular in the previous decade. Fashions changed, as well. Beginning in the late 1930s, the style we now call Retro or Retro Modern replaced the Art Deco designs of the 1920s and early 1930s. Retro jewelry was big, bold, and consisted mainly of metals. Warm yellow and rose gold colors dominated the Retro styles, largely replacing the white metals of the Art Deco period. The United States Department of Commerce played a role in the new popularity of heavily gold-plated jewelry by issuing Commercial Standard CS 47-34 which created a precise definition for “gold filled,” decreeing that the total weight of gold filled jewelry had to be 1/20 or more (5% or greater) 10K or higher karat gold.
Gold filled jewelry is made from karat gold which has been bonded to the surface of a supporting base metal through a process of fusing and rolling. It is always marked with the karat designation and an indication that it meets the legal standard. Look for marks such as 1/20 12K G.F. or 12 Kt. Gold Filled. Rolled gold plate is also made by fusing and rolling gold onto base metal, but the plating is significantly thinner. Rolled gold plate may be marked 12 Kt. R.G.P. or 1/40 12K R.G.P. Another mark you will sometimes encounter is G.E., or gold electroplate. This is the thinnest of all gold plating techniques. The gold or gold alloy is not fused and rolled onto the base metal beneath, but rather plated in solution using an electrical charge to make the bond. By law, gold electroplate must be at least 7/1,000,000-inch thick, but this is extremely thin when compared with gold filled.
The manufacturing of gold filled jewelry is a remarkable feat of technology! Two trade publication articles about this process dating from 1953 and 1958 supply a wealth of information, as well as some wonderful photographs. Here are the steps in the process:
1. Pure gold (24 karat) and alloy metals such as silver, copper, zinc, or nickel are meticulously weighed out in the correct proportions to create the desired karat gold.
2. The gold and alloy are melted in a crucible and then poured into a mold to form an ingot.
3. The karat gold ingots are rolled into rectangular sheets. These sheets are used like slices of bread to sandwich a “filling” of base metal such as bronze, brass, nickel, etc. A “dressing” of solder (usually silver and copper) is used to help the layers of the sandwich stick together firmly.
4. The “sandwich” is clamped between steel plates and guided into a gas-fired bonding furnace. Here it is heated to the melting point of the solder and that temperature is held absolutely constant until the gold is completely bonded to the inner reinforcing layer of base metal. This results in a gold filled ingot, which is then cooled slowly and evenly to maintain a perfect bond.
5. The gold filled ingot is put through a series of giant rollers which compress it into sheets of the desired thickness. Throughout this pressing and rolling, the precise proportion of karat gold to base metal is maintained and the thickness of the gold plating remains absolutely uniform.
6. Finishing rolls with a mirror-like surface create the final ultra-smooth finish of the gold filled flatstock sheets.
7. Gold filled tubes and wires are created through a similar process, with a machine known as a cupping and drawing press.
8. These mirror-finish gold filled flatstock sheets, tubes, and wires are then sent to the jewelry manufacturer to be cut and shaped into finished products. Tubes of various sizes can be used to make pen, pencil, or pill cases, as well as jewelry components. The gold filled wire is used to make chains, as well as jewelry elements.
Because of the unique properties created by this manufacturing process, gold filled jewelry has many advantages. It is stronger than karat gold jewelry because the inner core of base metal adds structural strength. It is extremely durable because the gold plating is so thick. Unlike rolled gold or gold electroplate, it is rare to see gold filled jewelry which has lost its gold plating. The luster of gold filled jewelry is generally excellent because the perfectly even thick karat gold plating produces the rich appearance of fine jewelry. More finely worked designs are possible with gold filled jewelry than with thinner plating or base metal because the thicker plating creates a malleable surface. Best of all, however, is the price difference between gold filled jewelry and fine karat gold. The development of this process brought the look of fine gold into the range of affordability for the masses at a time when the middle class was rapidly growing.
Restrictions were placed on the use of base metals during World War II, creating a dilemma for manufacturers of gold filled jewelry and their customers. It is not uncommon to see jewelry from this era marked 1/20 12K G.F. ON SILVER or STERLING + 1/20 12K GF.
Gold filled over silver should not be confused with vermeil, which is sterling electroplated with gold. While lovely in its own right, vermeil lacks the durability of gold filled. Vermeil has more versatility in design, however, because it can be used as a finish on cast jewelry.
Wartime materials restrictions caused some difficulties for manufacturers of gold filled jewelry even when it was possible to obtain base metals. The composition of the “filling” of the sandwich sometimes had to be modified by the manufacturer because of shortages. According to Walter Lampl, Jr., this occasionally created problems with “bleed-through” and color distortion.
The design and appearance of gold filled jewelry is heavily influenced by the types of gold filled stock available to manufacturers. Gold filled jewelry can not be cast in molds, and it is not generally deeply sculpted or heavy in weight. It is, necessarily, made from flatstock sheets and tubes or wires of various sizes. Within these design limitations, however, jewelry makers have always shown tremendous creativity.
Throughout the 1950s the sleekly elegant styles of the day and the desire for “real look” jewelry made gold filled an obvious choice. The jewelry industry strove to educate consumers about the definition and desirability of gold filled jewelry through various public information campaigns. Articles in trade magazines from that era discuss these marketing efforts, reinforcing the advantages of gold filled jewelry to retail jewelers. A November 1956 advertisement for Imperial Pearl Syndicate 12K gold filled pins, earrings, and bracelets demonstrates a keen understanding of the virtues of this type of jewelry from the customer’s point of view: “These newest Imperial creations are the highest points yet reached in fashion jewelry at modest prices…luxuriously combined with world-famous Imperial Cultured Pearls, they possess all the characteristics of costly 18K gold jewelry – even to the precious real gold surface that adds lasting wear. These are jewels you will wear often and treasure always.”
Gold filled jewelry continues to be manufactured today. The enduring popularity of this material demonstrates how well it has achieved the goals of those who first imagined it, those who labored to perfect the alchemy by which it is manufactured, and the artistry of the designers who have continued to shape it into jewelry which has satisfied the demands of fashion through many generations.
Fine Jewelry for the Millions: The Story of Gold-Filled…An Opportunity, Jewelry, September 1953.
S.L. Cantor, How “Gold Filled” Is Made, Jeweler’s Circular-Keystone, September 1958, p. 57-60.
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