Birthstone Lists

Month	Picture	Birthstone	Genuine Stone
January		Garnet	Garnet
February		Amethyst	Amethyst
March		Aquamarine	Bloodstone or Aquamarine
April		White Sapphire	Diamond
May		Green Spinel	Emerald
June		Alexandrite	Pearl or Moonstone
July		Ruby	Ruby
August		Peridot	Sardonyx or Paridot
September		Sapphire	Sapphire
October		Rose Zircon	Opal or Tourmaline
November		Golden Sapphire	Topaz or Topaz Quartz
December		Blue Zircon	Turquoise or Lapis Lazuli

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Anniversaries

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Stone Colors

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Why Does Gold Discolor Fingers?

You may think that faulty manufacturing or underkarating might be the problem when a ring "turns," blackening or discoloring the skin and clothing, or the jewelry itself. However, that is not the case.  The most common reason is metallic abrasion, caused by makeup on skin or clothing. Cosmetics often contain compounds harder than the jewelry itself, which wear or rub off very tiny particles. Very finely divided metal always appears black rather than metallic, so it looks like a jet-black dust. When this dust comes into contact with absorbent surfaces such as skin or clothing, it sticks, forming a black smudge. To prevent this, you might try switching cosmetics. If this is not possible, we recommend that you remove rings and other jewelry while applying cosmetics, and clean skin areas in contact with jewelry with soap and water.

Another cause is actual corrosion of the metals. Gold itself does not corrode, but its primary alloys of silver or copper will do so—forming very dark chemical compounds—under moist or wet conditions. When we perspires, fats and fatty acids released can cause corrosion of 14-karat gold, especially when exposed to warmth and air. This problem can be worse in seacoast and semitropical areas, where chlorides combine with perspiration to form a corrosive element that discolors skin. Smog fumes gradually attack jewelry and are evident as a tarnish that rubs off on the skin. We suggest that our customers remove jewelry often and use an absorbent powder, free of abrasives, on skin that comes into contact with jewelry. 

Even the design of jewelry can be an influence. Wide shanks have more surface area to contact abrasives or corrosives. Concave surfaces inside a shank form collection points that trap moisture and contaminants, also causing a type of dermatitis. To prevent this, remove all rings before using soaps, cleaning compounds or detergents, and clean their rings frequently. As well as solving the problem, you’ll be amazed at how much better your rings look! In addition to these corrective actions, perhaps you should switch to 18-karat gold or platinum. The lower alloy content of 18-karat gold—25%, versus almost 42% in 14-karat gold—significantly reduces the problem, and the use of platinum should eliminate it completely. 

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About Gold

Pure gold (fine gold) is softer than pure silver but harder than tin. It's beauty and luster are unmatched by any alloyed golds. The extreme malleability, ductility, and softness of pure gold make it practically useless for jewelry applications. 

The addition of alloying elements (other metals) to gold are used to increase the toughness and hardness of the metal. While almost any metal can be alloyed (melted) with gold, only certain metals will not dramatically change the color or make the metal brittle. The addition of indium, for instance, turns gold purple and gives gold the workability of glass. 

Over time, certain percentages of gold have become legally recognized "karats." The karat indicates the amount of gold as a percentage of the total, i.e. 24 karat is 100 percent gold. Thus 14 karat is 14/24's gold or 58-1/3 percent gold. Gold standards vary around the world. In the United States, 18, 14, and 10 karat gold are the only karats allowed to be sold as karated gold. In karated gold, there is a balance of metals in the non-gold percentage. These metals provide the various colors and hardness of karated golds. 

Typical alloying elements and their color effect are: Copper, Reddening; Silver, Greening; Zinc, Bleaching; Nickel, Whitening; Palladium, Whitening.  

Adjusting the proportions of coloring agents provides the array of colors on the market. Additional metals enhance properties such as castability, grain size, hardness, corrosion resistance, color, workability, ultimate strength, and others. These additions can dramatically change the properties of the karated metal for better or worse. 

Knowing how the additions will affect the metal greatly enhances the possibility of a superior final product. In deep drawing of metals, it is important to have a metal which will elongate or stretch a great deal before fracturing, thus high ductility. The requirement for an earring post would be a high tensile strength (a great deal of force needed to get the material to permanently deform, bend). It is imperative to select the proper karated composition for the desired application.   

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Chatham Gemstones

In 1938 Carroll F. Chatham made a remarkable discovery that revolutionized the jewelry industry. After years of research and determination, he uncovered the secret of growing emerald crystals in a laboratory environment setting. Chatham Created Emeralds are not simulates or imitations, but gemstones possessing the same properties as their naturally occurring counterparts. These unique processes, which duplicate the conditions deep within the earth where gem crystals grow, remain a carefully guarded family secret.

In the years since, the Chatham Research Laboratories have also developed the process for growing rubies, blue, orange and pink sapphires, alexandrite, opals and diamonds. Today, Chatham continues as the most innovative producer of fine quality gemstones in the world and has been featured on CNBC, Dateline Magazine (NBC), National Geographic TV Specials, The Discovery Channel, the BBC and hundreds of print articles including National Geographic Magazine, U.S. Scientific, Consumers Report, Readers Digest, The San Francisco Chronicle and Fortune Magazine.

All of these efforts and contributions of time and money are made for the following reasons; to keep the gemstone industry informed of scientific accomplishments wherever in the world they occur; provide the tools for learning in the form of donated stones for research and teaching; and helping the general public better understand the roll man plays today in bringing quality gemstones within the affordable range of the consuming public.

Q: Do Chatham stones and natural stones have the same properties?
A: Yes. To legally use the term "created", the emerald, ruby, sapphire, alexandrite, and opal must be the same chemically, optically, and physically as its natural counterpart. One came out of the ground, one from the laboratory environment.

Q: Are Chatham stones "synthetic"?
A: Yes and no. If to you synthetic means fake or imitation, then no, it is not synthetic. However, the official gemological definition of a synthetic emerald or other created stone REQUIRES the stone to be identical to the natural stone. Unfortunately, consumers rarely understand this archaic definition.

Q: How does one "create" a gemstone in a laboratory?
A: Natural gemstones are crystals that have formed deep in the earth by heat and pressure. Chatham recreates a similar heat and pressure environment using the same natural elements and even some of the natural gemstone as well, and nature does the rest...over a 10 to 14 month growth cycle. Chatham "creates" the opportunity for growth to occur, much like the flower grower does in a hot house.

Q: Can you tell the difference between Natural and Chatham Gemstones?
A: Only a trained gemologist can positively separate our stones from their natural counterpart through the study of inclusions and trapped crystal imperfections which reflect where every crystal was "born". Stones from Colombia can be separated from Brazil, and those two locations from Africa. No more obvious are the clues in a Chatham stone.

Q: Is a Chatham stone like a cultured pearl?
A: Yes. Just as man provides the nutrients and controlled environment to help grow a cultured pearl, Chatham provides the natural elements and controlled environment to grow crystals. The culturing starts on a round ball surgically implanted in the oyster's mantel tissue. The culturing of emerald, as one example, starts from a thin slice of natural emerald or beryl. This is later removed from the Chatham stone but the pre-form ball stays in the cultured pearl.

Q: Does Chatham put in the inclusions?
A: No. Chatham strives for the best quality, but since nature is responsible for the crystal growth, some inclusions may be present and reflect the naturalness of the product.

Q: Is the color of any Chatham stone enhanced or treated in any way to improve appearance?
A: No. While treatments to natural emerald, ruby and sapphire are the norm to day; Chatham has not followed this trend. All Chatham stones are natural in color and clarity. In fact, we are so proud of our quality, we guarantee it for life!

Q: Is there a difference in price?
A: Yes. Natural emerald may cost up to $30,000 per carat. The equivalent Chatham stone would be less than $1000 on average. On the other end of the scale, there are many "emeralds" of very poor color and quality available for $1 per carat. Chatham does not release poor quality stones.

Q: Why should I buy a Chatham Created Gem?
A: The demand for quality natural gemstones has never been greater, and the supply never more scarce. This drives the prices skyward to prohibitive levels. Chatham brings you the beauty of the natural gem at prices you can afford.

Have more questions? Feel free to contact Chatham.com and ask away. A trained gemologist is always on staff to answer your questions or guide you to an outlet nearest your location.

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