Precious Metals Learning Guide

Gold Quality

The purity of gold is measured in karats. Pure gold measures 24 karats but is too soft in this state to be used effectively in jewelry. So it is alloyed with other metals--silver, copper, nickel, and zinc--to increase its strength and durability. Common measurements once the alloy is added are 18 karat (75% gold), 14 karat (58%), and 10 karat (47.7%). In the United States, the legal karat limit for the metal to still be considered gold is 10 karats. A higher karat measurement in gold content indicates a greater value of the jewelry piece. Gold jewelry should always be stamped with the karat mark, either 18k, 750 (European marking for 18k), 14k, 585 (European marking for 14k), or 10k. In addition, to assure its quality, the piece should be stamped with the manufacturer's trademark or country of origin.

Gold Color
Yellow gold is the most common color and is usually alloyed with silver and copper. Yellow and white gold are similar in strength and malleability, making them perfect for jewelry that is worn daily. White gold is alloyed with nickel, copper, and zinc--and while it looks similar to platinum, it has vastly different properties. Rose-colored gold is alloyed with copper and is often used to accent white or yellow gold. The saturation of color varies from piece to piece and according to gold content.

Gold Care
To keep gold shining and scratch-free, avoid contact with chlorine and other harsh chemicals. Do not wear jewelry during rough work and be sure to store it in a fabric-lined jewelry box or pouch. To clean gold jewelry, use warm water, a mild soap, and a soft bristled brush, if needed.

Silver


Silver Quality
Pure silver is soft and easily damaged. To give it more durability when creating jewelry, it is combined with copper, which makes it sterling silver. Sterling silver is 92.5% silver and 7.5% copper, but this alloy does not have an effect on the value of the metal. To ensure that the silver is high quality, jewelry should be stamped with a quality mark. According to federal law, the mark must be accompanied by a registered trademark or maker's mark. Acceptable marks for silver include: sterling, sterling silver, ster, .925.

Silver Care
Silver should not come into contact with harsh household chemicals such as bleach, ammonia, or chlorine. To avoid scratches, store silver in a jewelry box or pouch. Silver tends to tarnish as it reacts with sulfur or hydrogen sulfide in the air. Cleaning and wearing it regularly will help maintain its shine and prevent this. Immediately upon noticing discoloration, use a polish made specifically for removing tarnish.

Platinum

Platinum Quality
Platinum is the most durable of fine jewelry metals. It does not chip or splinter easily, making it perfect for diamond and gemstone settings. It is similar in color to white gold, but compared side by side, the difference is clear. Platinum jewelry is usually 95% pure platinum with 5% iridium or palladium alloy. It can also be 90% pure platinum with 10% iridium or palladium alloy. To guarantee its quality, each piece should be stamped with a 900 Plat to denote 90% platinum or a 950 Plat or Plat mark to denote 95% platinum.

Platinum Care
Cleaning platinum jewelry with mild, soapy warm water should be sufficient to maintain the metal's shine and polish. As with other fine jewelry, it should be stored in a fabric-lined box. Do not wear platinum while doing rough work, and avoid contact with harsh chemicals. If platinum becomes scratched or a patina begins to develop, a jeweler can restore the original shine.

Gemstone Learning Guide

Color
Jewelers describe the color of a gemstone in terms of three characteristics: hue, saturation, and tone. A gemstone's basic color is its hue, and those with purer hues (for emeralds, green; for sapphires, blue; and for rubies, red) are generally considered more valuable. Often, however, a hint of another color can be detected. Sapphires will range from purplish blue to greenish blue; emeralds, yellowish green to bluish green; and rubies, orangey red to purplish red. Saturation is a measure of the intensity or purity of a gem's hue and is determined by the degree to which gray or brown hues mute its defining color. Value tends to increase with saturation, so a fully saturated purplish blue sapphire may well be more expensive than a muted pure blue one. The tone of a gemstone, a measurement of its lightness or darkness, is usually given as light, medium-light, medium, medium-dark, or dark.

Clarity
A flawless gemstone is rare and usually extravagantly priced. As with diamonds, most gemstones have inclusions, or tiny mineral flaws, that can be seen under magnification or by the careful eye. Sapphires tend to be moderately included, while emeralds and rubies are usually heavily to moderately included. Make sure that any inclusions in the stone do not penetrate deeply into the gem, as this may cause it to break or crack. Clarity grades range from VVS (very, very slightly included) to I3, in which inclusions are prominent and severely affect the gemstone's beauty.

Cut
A gemstone's cut refers to its proportions and symmetry. It is essential in making a gemstone look appealing--the stone should be symmetrical in all dimensions so that it will appear balanced, and so that its facets will reflect light evenly, providing good brilliance. Color should also be taken into account when cutting for optical efficiency. If a stone's color is highly saturated, a shallow cut will allow it to pass more light, while a deeper cut may increase the vividness of a less saturated gem. There is no generally accepted grading system for gemstone cut.

Size
Though a gemstone's weight is usually given in carats, this may not give an accurate idea of its size, because different types of stone have different densities. Therefore, a 1-carat sapphire or ruby will be smaller than a 1-carat emerald, though they have the same weight, because sapphires and rubies (both a form of the mineral corundum) are more dense than emeralds.

Illustration of gemstone dimensions

Gemstones can also be measured in dimensions (diameter, length, and width). It is important to know the dimensions to ensure that the gemstone weight will be visible and well proportioned in the setting.

Treatment
Gemstones are often treated to enhance color and fill cracks. Please note that, if a gemstone has been treated, this information will be provided in the specifications on the stone's product detail page. There are various accepted techniques, depending on the type of stone. For example, oils and resins are frequently used to fill surface-reaching fissures in emeralds and rubies. This process is not permanent, however; if a treated ruby or emerald is subjected to high heat from a jeweler's torch, an ultrasonic or steam cleaner, or even hot dishwater, the filler may leak out of the stone. Sapphires and rubies are often heated in a kiln or furnace to enhance their color. Such heat treatment, which is considered permanent, has been used for centuries. Lightly colored sapphires may also undergo diffusion treatment. This is done by heating a stone in the presence of coloring elements such as titanium or iron, which causes a thin layer of color to be diffused into the stone's surface. Because this color layer is so thin, a diffusion-treated sapphire should not be repolished.

Care
To clean gemstone jewelry, first wipe it with a soft cloth to remove any dirt. Emeralds require only the use of a soft cloth, as cleaners may damage these soft gems. Sapphires and rubies can be cleaned with either an ultrasonic cleaner or a solution of one part ammonia to six parts water, with a soft brush. Store your gemstone jewelry in a soft cloth pouch or jewelry case so it does not touch other pieces in your collection. As with all jewelry, normal wear and tear can loosen prongs and settings, so it is a good idea to have it checked by a professional jeweler who can make repairs as needed.

Watches Learning Guide

Mechanical Watches
Mechanical watches are the traditional "wind-up" or analog watches with numbers or marked dials and moving hands. They are powered by a mainspring and operate via a series of interlocking wheels and gears. To set the gears in motion, mechanical watches must either be wound automatically or by hand. The automatic watch is wound continuously as the owner wears it: when the wrist moves, a rotor, or weight, inside the watch drops by the force of gravity, causing the mainspring to be wound. Since the mainspring of an automatic watch maintains full tension for a longer period of time than a hand-wound watch, it has greater consistency of power and, therefore, greater accuracy.

The moving parts or bearings of better-quality watches are usually called "jewels." Because the gears and wheels are subject to wear, the bearings are made of hard synthetic sapphires or rubies. Mechanical watches tend to be more expensive than electronic quartz watches due to the high-quality bearings, smaller production rates, and distribution.

Electronic Crystal Watches
An electronic quartz watch is a battery-powered watch that contains a tiny quartz crystal that vibrates to measure time. Usually the crystal is synthetic quartz and vibrates over 32,000 times per second. This high number of vibrations gives quartz watches extraordinary precision--many are capable of accuracy to within one minute a year. Quartz watches have fewer moving parts than mechanical watches and are less likely to break down over time.

Quartz Crystal Watches
The quartz digital watch displays time using numerical digits in an LCD (liquid crystal display) instead of moving hands. A battery causes the quartz to vibrate and a computer chip translates these vibrations into the display. These operate with the same accuracy as electronic quartz watches.

Water Resistance
Most watches on the market are water resistant. A watch should be marked "water resist" to confirm its level of resistance to moisture, as there are several degrees of resistance. This information is called out in the product specifications on the detail page of every watch that Amazon.com sells.

Water resistant: It is wearable if water is being splashed, but it should not be exposed to any water pressure. It is protected from perspiration or accidental immersion in water.

Water resistance 50 meters (150 feet): It is wearable around household sinks, while playing sports, and in shallow water. It should not be worn while scuba diving.

Water resistance 100 meters (333 feet): It is wearable around household sinks, while playing sports, and while swimming or poolside diving. It should not be worn while scuba diving.

Water resistance 300 meters (990 feet): It is wearable around household sinks and while playing sports, swimming, and scuba diving at depths not requiring helium gas.

Gray-Market or Unauthorized Watches
Gray-market watches are genuine watches from the original manufacturer that were acquired from an unauthorized dealer or reseller prior to customer purchase. Manufacturer warranties are not valid for these watches.

Watch Care
Watches can easily be soiled by sweat or dirt. To keep them clean, wipe the face, case, or band regularly with a soft cloth, paying special attention to the back of the case. Leather bands should be wiped with a soft cloth, but metal bands can be cleaned with soapy water and a soft brush. Watches should not be left in extreme temperatures, as this could damage the watch or shorten the lifespan of its battery. If your watch is an analog quartz watch, do not expose it to magnetism--it may temporarily stop working or show a time loss or gain. To sustain water resistance, have your watch checked regularly and maintained according to manufacturer instructions.

Pearl Learning Guide

Cultivation
Pearls are produced naturally in the body of salt and freshwater mollusks, such as oysters and mussels. When these animals sense an irritant, such as a grain of sand, they produce a soft coating of calcium carbonate substance around it. The result is a pearl. Because perfectly round, naturally produced pearls are so rare, a process known as cultivation was developed by Kokichi Mikimoto in the early 1900s. A small bead of polished shell, the nucleus, is used as an irritant and delicately inserted into the mantle of a mollusk. It takes approximately 20-24 months of intensive husbandry to cultivate a saltwater pearl and somewhat less time to cultivate freshwater pearls. The harvest usually takes place during the months of June and September.

Color
Mollusks produce pearls in a variety of colors, accommodating most personal preferences and budgets. The general color of a pearl is also known as the body color. Pearls typically range from white, cream, and yellow to pink, silver, or black. An overtone of secondary color is sometimes seen. For instance, a pearl may appear to be white, but upon closer inspection a rosy hue is detected. The body color would then be termed white-rosé. Color variation does not affect the quality of the pearl, though it should be noted that color matching is important when choosing pearls for some necklaces, earrings, or bracelets. In fashion jewelry, pearls can sometimes be dyed to achieve the desired color, which should be mentioned in the product description or specifications.

Pearl colors


Lustre
The appealing, deep shine of a pearl is often what defines its beauty. This shine is produced by multiple layers of semi-opaque calcium carbonate crystals, called nacre. The nacre reflects light on the surface of the pearl, producing brilliance and sheen. Lustre is an integral feature in determining the quality of a pearl. Large pearls have a thicker nacre and, therefore, a higher lustre. When comparing a small Freshwater pearl to a large South Sea pearl, the difference is clearly visible to the untrained eye and should be considered when purchasing pearls.

Examples of pearl lustre


Shape
While pearls come in many different shapes, the rarest and highest-quality are round. Akoya, Tahitian, and South Sea oysters tend to produce the roundest pearls, while those of Freshwater mollusks can be oval to slightly off-round. When considering a pearl purchase, whether it be a necklace, bracelet, or earrings, look for consistency in the shapes of the pearls. Many of the less symmetrical shapes are used in stylish jewelry which can be quite beautiful: the drop pearl’s shape lends well to earrings, and the baroque pearl features irregular shapes that work well as necklace accents. In addition, a half sphere pearl called a “mabe” is often used in earrings, necklaces, and bracelets.

Examples of pearl shapes


Size
An oyster’s particular type and size has a direct effect on how large the pearl it produces will be, and pearls do come in a wide range of sizes. Round pearls are measured according to their diameter, while baroque pearls are measured by their length and width. A pearl’s size does not necessarily affect its quality, but it does affect its price. Large, round pearls are rare and their lustre is usually high--this beautiful combination of traits is often reflected in the cost of such pearls.

Average pearl sizes (in diameter):
Akoya: 6-8mm
Freshwater: 5-6.5mm
South sea: 11-13mm
Tahitian: 11-12mm

Illustration of pearl sizes


Surface Markings
Often when an oyster creates a pearl, the nacre does not develop smoothly. The surface of a pearl is judged by how many marks are visible in the nacre. These imperfections can be small and unnoticeable or quite large and distinct. Like diamonds, pearls are rarely flawless. However, high lustre or the way pearls are strung and set can help conceal surface markings.

Examples of surface markings


Akoya Cultured Pearls

Akoya pearls are produced in several varieties of saltwater mollusks in Japan and China. They were the first to be cultured in the early 1920s and are the most popular pearls used in strands and earrings. They produce the most consistently round pearls with high lustre and very slight imperfections. Their colors range from cream and white to white-rosé. Initially, they look similar to round Freshwater pearls, but compared side-by-side, the difference in lustre and color is obvious.

Freshwater Cultured Pearls

These pearls are gathered from freshwater lake and river mollusks. Most Freshwater pearls come from China and they can be mostly round to off-round, or rice-shaped to baroque. They look similar to Akoya pearls, but are the perfect gift when on a budget. They might be slightly less symmetrical, smaller, or not as easily matched, but these minor differences provide a major value for the price.

South Sea Cultured Pearls

South Sea pearls are primarily cultured in the northern waters of Australia, the Philippines, and Indonesia. They are either white or black with silver overtones. Because of their size and high lustre, and the sensitivity of the oyster to culturing, they are quite valuable and rare. They average from 11-13mm, but can even be found as large as 20mm. The oyster that produces these pearls is considerably larger than those that produce Akoya pearls, and is extremely sensitive to the cultivation process. Gathering acceptable South Sea cultured pearls from these oysters is difficult, and makes them more expensive than Akoyas.

Tahitian Cultured Pearls

The natural black color of the Tahitian pearl comes from the black-lipped variety of the pinctada maxima oyster. These oysters are farmed on the volcanic atolls of Tahiti, where the mixture of nutrient-rich ocean water mixes with warm lagoons creating an ideal environment for them--and the only place where Tahitian pearls can be found. Like the South Sea pearl oyster, the black lipped pinctada maxima is sensitive to the cultivation process, making the Tahitian pearl rare and expensive. Though they are, on average, slightly smaller than the South Sea pearl, Tahitian pearls are larger than Akoyas and their black color adds a dramatic touch.

Care
Proper care of pearls is not difficult if you remember that they are organic and produced by a living thing. Pearls are soft and delicate, but when cared for with common sense, they will maintain their lustre for centuries. The pearls should not come in contact with cosmetics, hairspray, perfume, chlorinated water, or other harsh chemicals. To keep them clean, let them be the last item put on when dressing, and the first item taken off at the end of an evening. The best way to maintain their lustre is to wear the pearls often, and wipe them down with a soft cloth afterward--pearls absorb the oils from skin, which helps keep them moist. Pearls should be stored in a cloth pouch or jewelry bag, separated from other jewelry to prevent nicks or chipping. Periodically, pearl strands should be restrung since the silk thread used to tie the pearls together breaks down over time.

Necklace Length Guide

Whether you're giving a gift or purchasing a new piece for that special evening out, consider where the strand or pendant will lie on the chest.

14k White Gold Journey Diamond Heart Shaped Pendant (1/4 cttw, H-I Color, I1 Clarity)

This elegant multi-stone diamond pendant is designed to represent the notion that love is a journey shaped by time and experience. Twenty-three individual diamonds, with a total weight of 1/4 carat, are graduated in size and arranged in shared prong settings of 14 karat white gold to form a simple heart design. Much as a three-stone diamond symbolizes your past, present, and future as a couple, a journey diamond represents the continual growth of your love. The open design of this pendant is a reminder that the story of your life together is still unfolding. This beautifully-designed pendant makes a meaningful gift for an anniversary or other special occasion. It is showcased on a delicate and brightly polished white gold box chain that measures 18 inches and fastens with a spring ring clasp.

Heart Earrings: 14K White Gold

Ultra-sleek heart shaped earrings shine with modern sophistication in lustrous 14K white gold and dazzling diamonds. An attractive pair of diamond heart earrings is always appropriate and adds elegance to even the most casual outfit.

14K White Gold & Diamond Angel Charm

An angel to watch over you. This adorable 14K white gold angel charm features sparkling round diamonds to catch the eye. A spring ring clasp makes it easy to add and removal from your charm bracelets. Made in Italy. Weight is 1.0 gram.

18k Gold, Round, Diamond 4-Prong Stud Earrings (1/3 cttw, H-I Color, SI1-SI2 Clarity)

No jewelry wardrobe is complete without a classic pair of diamond stud earrings. Simple enough for daytime wear, yet radiant with evening attire, they offer sophistication and versatility all in one beautiful package. These classic studs, available in 18 karat white or yellow gold, showcase single round-cut diamonds with a total weight of 1/3 carat, held securely in four-prong settings. They are featured on posts with friction-back closures.

These are fine quality diamonds, with exceptional brilliance. They are near-colorless, with a minimum color rating of H-I, and appear white to the eye. The clarity rating of these diamonds is Sl1-2, meaning there are small inclusions that can be seen somewhat easily under 10x magnification. These inclusions are not visible to the unaided eye, however, and the diamonds appear clear in the mounting.

10K Gold Men's Onyx Claddagh Ring

his very stylish ring depicts an Irish symbol for friendship and love. This ring is crafted from 10k white gold and features a gorgeous design with hands embracing a heart crowned with three sparkling round diamonds equaling .03 ctw. The ring weighs approximately 5.5 grams. The Perfect Friendship Ring.

Sterling Silver 1.00 Carat Diamond Tennis Bracelet - 7.2"

Wrap your wrist in luxury! This diamond tennis bracelet is created from Sterling Silver, measures 5.8 mm. and 7.2 inches in length, weighs approximately 16.5 grams. Total Diamond Weight - 1.00 Ctw.