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Gold Jewelry Article 30: Rare and Precious Gold and Platinum Buying Guide

Jewelry and gems, The Buying Guide

Rare and Precious: Gold and Platinum

Gold: The timeless choice

Gold jewelry is very popular today and available in more styles, colors, and finishes than ever before. It is also a popular choice for setting gemstones. But it is very important to understand gold, and differences that affect price, in order to avoid confusion about the wide range of prices that seems to pervade the market for what may appear to be the “same thing.” As with gems, wherever there are significant price differences there are usually quality differences. The key to getting value in gold is understanding what accounts for differences in quality and price.

What is gold?

Gold is one of the world’s most precious metals. It is so soft and workable that one ounce can be stretched into a five mile long wire, or hammered into a sheet so thin that it could cover a hundred square feet. It is one of our rarest metals, and since pure gold doesn’t rust or corrode, it can last forever. Interestingly, gold is present almost everywhere around us; in the earth’s crust, in seas and rivers, and in plants, but it is very difficult and expensive to extract. Approximately two and a half to three tons of ore are needed to extract one ounce of gold.

Most gold used in jewelry is an alloy

Gold is the most popular metal used for jewelry today. The simple gold wedding band probably accounts for more of the world’s gold than any other single type of jewelry. But pure gold is very soft so it is usually mixed with other metals to make it stronger and prevent it from bending too easily. When two or more metals are mixed together, we call the resulting product an alloy. Most gold used in jewelry is an alloy; and the metals added to the gold are also called “alloys.”

What is a Karat? Or is it Carat?

In jewelry, the term carat (or, Karat) has a double meaning: carat is used as a measurement of weight for gemstones, with one carat weighing 1/5 gram; carat is also used in countries around the word to indicate the amount of pure gold in a piece of gold jewelry. In the United States, however, when using the word to indicate gold content rather gemstone weight, it is spelled with a “K;” hence “karat,” to avoid confusion. Jewelry should always be marked to indicate how much pure gold it contains. In the united States a karat mark, abbreviated to K or KT, indicates the amount of pure gold present in the metal. The word karat (carat) is derived from the word for fruit of the carob tree: in Italian, carato; in Arabic, qirat; in Greek, keration. The seeds of the fruit were used in ancient times for weighing gems. Also, the pure gold Byzantine coin cald the solidus weighed 24 karats. therefore, a 24 karat mark (24K or 24KT) became the mark used to indicate that something was pure gold. To understand the concept as applied to gold, imagine that, “pure gold” is a pie into 24 equal “slices” or parts. Each karat equals one part of the pie. So, 24 KT would mean that 24 parts (out of a total of 24) are gold. In other words, 24 KT would be 100% gold; or, pure gold. In the 18 karat gold jewelry, 18 parts are pure gold and six are another metal (or, 18/24 = 3/4 = 75% pure gold); in 12 karat, 12 parts are pure gold, 12 parts another metal (12/24 = 1/2 = 50% pure gold). And so on. I some cultures, 24 karat gold jewelry is required for certain jewelry pieces, but it’s generally agreed that 24 karat, or pure gold, is too soft for jewelry use. In some parts of the world, 18 KT 0r 20 karat is preferred because of its brighter yellow color and because it is considered “purer” and more precious. In the United States, we prefer 14 or 18 karat gold because it is more durable than higher karat gold. We caution clients about the risk of high karat gold (20 KT, 22 KT, or 24 KT) for a gem-studded setting because prongs can be too easily bent open accidentally, resulting in the loss of the stones. In some countries such as Italy, the percentage of pure gold is indicated by a number representing how many parts; out of a total of 1,000 parts, are pure gold. One thousand parts would be the equivalent or 24 karat; 750 means 750 parts of 1,000: 750/1000 = 75/100 = 75% pure gold. This corresponds to 18 KT.

A word about Russian marks

Old time pieces made in Russia were marked to indicate the content on its equivalent to a “zolotnik.” A piece marked 96 contained as much gold as 96 zolotniks, which equals pure gold; 72 equals 18 KT (750); 56 equals 14 KT (585).

To be called gold, what is the minimum gold content?

Many countries have established minimum standards that must be met for items to be legally called “gold.” The laws governing the actual content of gold required in piece of jewelry, however, vary. In the United States, to be called “gold,” the item must be at least 10 KT; in England and Canada, 9 KT; in Italy and France, 18 KT.

The many colors of gold

Pure gold is always yellow. But because pure gold is too soft for most jewelry use, and must be mixed with other metals (alloys) to increase its hardness, the color can also be modified by adding varying amounts of these other metals. Those usually added to gold for jewelry use include copper, zinc, silver, nickel, platinum, and palladium (a metal in the platinum family). Depending upon which alloys are used, a variety of colors can be produced. Another practice is to plate 14 KT gold jewelry with 18 KT for an 18 KT look, that is, a stronger yellow color. White gold is also frequently plated with rhodium, a rare and more expensive metal from the platinum family, to create a whiter, brighter finish.

Some people are allergic to nickel and should not wear white gold containing nickel. For this reason, a white gold alloyed with palladium is being used by some manufacturers. White gold that contains palladium will be more expensive than yellow gold or white gold containing another alloy. But it is still less expensive than platinum.

What causes skin discoloration with some gold jewelry? Pure gold doesn’t tarnish and won’t discolor the skin, but alloys in the gold can corrode and produce discoloration to the skin in contact with the gold, especially under moist or damp conditions. Fats and fatty acids present in perspiration can set up a corrosive reaction, and the problem can be worse in warm, humid areas, especially where chloride (salt) is in the air. Smog can also be a problem. Smog fumes can introduce chemicals that cause the alloys in gold to tarnish. The tarnish then rubs off, discoloring skin or clothing. Cosmetics may be culprit. Another common cause of discoloration is metallic abrasion caused by some makeup. Some makeup contains compounds that are actually harder than the jewelry with which it comes into contact. As the harder compounds rub against the jewelry, they cause tiny particles of metal to flake off, forming a darkish looking dust. When this dust makes contact with a soft, absorbent surface such as skin or clothing, it forms a black smudge.

There are several possible solutions to the problem of skin discoloration. First, get into the habit of removing jewelry often and cleaning the skin that has been in contact with it with soap and water. Keep your jewelry clean as well, and wipe it periodically with a soft cloth to remove tarnish. Next, try using an absorbent body powder, one free of abrasives, on all areas of your skin that are in contact with jewelry.

Pay attention to the design of jewelry you select if skin discoloration seems to be a problem; wide shanks can cause perspiration, and rings with an inner concave surface can cause moisture and contaminants to collect, causing both discoloration and dermatitis.

finally, try switching to a higher gold content or to a different manufacturer. The higher the gold content, the less likely it is that discoloration will occur because in the higher karat gold there is less of the alloy, such as copper, silver, nickel, that might corrode. People who have a problem wearing 14 KT gold jewelry may find that the problem disappears with 18 KT gold.

Sometimes simply changing to a similar product by a different manufacturer may solve the problem. This does not mean that one product is inferior to the other. Manufacturers often use different combinations of alloys, or different percentages or ratios of alloys. They may look the same, but you might find you can wear one manufacturer’s line better than that of another.

Since different metals, and different ratios, are used to produce different colors, discoloration may result when wearing one particular color or gold, but not when wearing other colors. If there seems to be a problem when wearing white gold, try white gold alloyed with platinum rather than nickel, since platinum won’t corrode.

Determining value requires more than scale!

- Weight is one factor that goes into determining the value of a piece of gold jewelry. Gold usually sold by weight, in grams or pennyweights. There are 20 pennyweights to one ounce; if you multiply grams by 0.643, you will have the number of pennyweights. Weight is important because it is an indication of the actual amount of pure gold in the piece. However, it is only one factor only to consider. When buying gold from a gold manufacturer, for example, factored into the price per gram is the cost of gold PLUS the cost for labor and workmanship. The price always takes into consideration: 1) The type of construction,
2) The means of production, and
3) How the piece is finished.

- Design and construction is important not only because of the piece’s finished look, but also because specific details in the overall design and construction affect comfort, wear-ability, and ease in putting the piece on or taking it off. Good design requires excellent designers, and extra care and attention to small mechanical details. This adds to the cost of any piece of jewelry.

In addition, jewelry design is also becoming recognized as an “art,” and jewelry designers as “artists.” some award winning designers command top dollar, as do top painters, sculptors, and other artists. A piece of gold jewelry made by a fine designer, especially if it is a one-of-kind or limited edition piece, will sometimes sell for much more than another piece of mass produced gold jewelry of the same weight and gold content. In looking at a piece of gold jewelry, you must also consider the type of construction necessary to create a particular design or look. Is the construction simple or complex? Did the piece require extensive labor or minimal labor? Did it require special skill, talent, or equipment? To ignore the design and construction factors and assign a value to apiece of gold jewelry based on gold content (i. e. 14 KT, 18 KT, etc.) and weight alone would be equivalent to placing a value on a painting based on the cost of paint and canvas alone.

- Production can affect price significantly. Is the piece produced by machine or by hand? The type of construction required to create a particular design may require that it be made entirely, or in part, by hand, while others can be completely made by machine. Some designs may be produced either way, but those done by hand will have a different look, and cost.

- Finish is where we take into account the care and labor costs associated with the actual finishing of the piece. For example, are there any special skills or techniques required to put on the final touches that make the piece distinctive, such as engraving, milgraining, hammering, or granulation? here we also need to note whether or not the piece has been carefully polished to remove any scratches that might diminish its beauty, or rough edges that might be abrasive or catch or snag on fabric. Consider whether the item was hand polished or machine polished; some pieces are machine made, but finished by hand. We must also take into consideration any special finishes to the metal itself, such as a florentine, matte, or sand blasted finish. Each step in the process, and each special step or skill required, adds; sometimes dramatically, to the cost.

Adding it all up

Many pieces of gold jewelry look alike at first glance. When examined carefully, however, if often becomes clear where the difference lie, both in quality and cost. Ask your jeweler to help you understand these differences by comparing different qualities for you. Only after carefully evaluating all these factors can you appreciate gold jewelry and recognize cost differences and real value.

Is that “Bargain” really a bargain?

Beware of underkarating, which is a serious problem around the world. If a piece of gold jewelry is underkarated, it means that the jewelry is marked to indicate a certain gold content, but actually contains less than is indicated. Needless to say, retailers who knowingly sell underkarated gold jewelry create the impression that they are giving you a bargain because their prices are so low, but if there is actually less gold ( and more alloy, so the piece would have a comparable weight to the others you might be considering), you aren’t getting any bargain. Unfortunately, most people never learn that they have bought underkarated gold. Thus, it is very important to buy gold jewelry from a reputable source, one that makes the effort to check its gold shipments carefully.

Look for a manufacturer’s registered trademark. Being sure gold is properly represented in terms of its value is what really matters; you should get what you pay for. Buying from a reliable source is the first step. In addition, be sure to look for a manufacturer’s registered trademark, a mark stamped near the karat mark. To avoid being held liable themselves, more and more jewelers are buying only from manufacturers willing to stamp what they make with their own mark, a mark registered with the U. S. Patent and Trademark Office. Buying gold with a “manufacturer’s trademark” is one way to help assure you get what you pay for, since the product can be traced to a specific manufacturer, whose name and reputation are on the line. Fine, expensive gold jewelry should always be tested. While testing for exact gold content requires assaying, it is usually relatively easy to detect any underkarating that is serius enough to affect the value of a specific piece of jewelry and the price paid. Any jeweler or gemologist appraiser can make such determination, in most cases, quickly and easily with only a gold tester or by using the streak test. You should be aware that an electronic gold tester, some very heavily plated pieces might give a false reading indicating gold when the piece is only base metal. For this reason the streak test is better but the person doing the test must be sure to take a file or carbide scriber and make a very deep scratch in order to penetrate the plating for an accurate test.

There are strict laws pertaining to gold content and marks used to indicate it. Take the time to understand what you are buying, buy only from a reputable source, and be sure to have it tested. If you do, your gold jewelry will give you a lifetime of pleasure.

Platinum: cool, classic, and contemporary

Platinum, which has been used in jewelry since the turn of the century, became especially popular during the Edwardian period because its malleable character made it a natural for the intricate and lacy work style of the day.

Platinum is frequently used in finest jewelry and to set the most valuable gems because it’s more “workable” and easier to move the prongs or setting around the stone, thereby reducing the risk of accidentally damaging it. Long a favorite for classic looks and for the finest diamond settings, platinum is now evolving as the metal of choice for design trends; sleek, bold, contemporary looks for brooches, necklaces, chains, and earrings. Sometimes platinum is alloyed with another metal to create an interesting color, or used alongside gold to create an innovative look.

Nothing is purer than platinum

Platinum is even more rare and valuable than gold. The platinum family is composed of six elements; platinum, palladium, iridium, osmium, rhodium, and ruthenium. These six silvery white metals are generally found together in nature, with platinum and palladium the most abundant, and osmium, rhodium, and ruthenium the rarest.

Platinum is rarest and heavier than other precious metals and as the purest, it’s sometimes referred to as the “noblest.” Most platinum jewelry also contains small amounts of the rarer and more expensive elements iridium or ruthenium for added strength.

Because platinum is so pure, it rarely causes allergic reactions. This is greatly appreciated by those sensitive people who experience reactions to or skin discoloration from jewelry containing base metals. In addition, platinum is somewhat stronger than other precious metals.

Platinum is identified by karat marks. In the United States, the abbreviations PT or plat indicate platinum. In Europe the numerical marks 950 or PT950 indicate platinum. The finest jewelry often uses platinum mixed with 10% iridium or ruthenium for added strength. This cost more since these are rarer and costlier metals.

Rhodium plating

Rhodium, another member of platinum family, is the brightest and most reflective of all the platinum metals. Rhodium is also harder and whiter than platinum and, because it is so durable, doesn’t wear off quickly, as does gold plating. A a result, it is often used to coat gold and platinum jewelry.

Rhodium plating should be considered especially for people who have allergic reactions to 10 KT or 14 KT gold, since it can help eliminate reaction to the alloys.

Yellow gold, white gold, or platinum: Which one?

To decide whether or not you want yellow gold, white gold, or platinum, you must first decide which color metal you prefer. This selection usually depends on personal preference, skin tone, and the color of other jewelry you may own. If your choice is yellow gold, keep in mind that it is available in several different shades, including a pure yellow, a pinkish yellow, and greenish yellow.

If you decide yellow is the color you want, then you must decide whether to get 14 Karat or 18 Karat. Certainly, 14 KT is more affordable than 18 KT; it is also harder. But the yellow won’t be as bright. If you refer a brighter yellow, we recommend that you ask your jeweler for a 14 KT gold with an 18 KT finish, that is, an 18 KT coating over the 14 KT. After several years the finish may wear off, but it can be re-plated foe a minimal charge.

If you prefer a white metal, your choice may be more difficult. Even though white gold and platinum may be similar in appearance, they are very different metals. As we mentioned, platinum is much more expensive, so if you’re on a limited budget, white gold may be the sensible choice. White gold is very hard and very resistant to scratching but exhibit a brownish or yellowish cast which must be covered by rhodium plating. As we mentioned, this plating will eventually wear off, although it can easily be re-plated.

One significant disadvantage of white gold is that it is more brittle than platinum or yellow gold. So if you decide on white gold, be sure to have your jeweler check the setting; especially prongs, at least once a year. Platinum is somewhat softer and more malleable than white gold, making it an ideal choice for very intricate settings that require intensive labor. It is much easier to use platinum for pave work, that is, designs in which the stones are set as closely together as possible, With platinum, the jeweler can also make a safer setting because a larger prong can be used, since platinum conforms so easily to the shape of the stone, reducing risk of damage. Over time, platinum also holds up better than gold One disadvantage of platinum is that many jewelers do not have proper equipment to work with it. This, combined with platinum’s cost, results in more limited variety of styles from which to choose. If you like basic classic design, you shouldn’t have a problem finding a setting you like. But if you need custom work to get the look you want, it can add substantially to the cost of the finished piece.

In final analysis, it is up to the individual to weight the relative advantage and disadvantage of gold or platinum. Whichever precious metal you select, there are many beautiful styles and designs from which to choose.

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