Gemstones can be broadly classified into 2 categories: precious and semi-precious stones.

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Sophia Shelton
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1 Welcome to the wonderful and fascinating world of Gemology. Welcome to a world where art and science merge! Enjoy the course! The information provided will give you a good understanding of gemstones and Jewelry. When you are ready, we highly recommend taking the certification test from Universal Gemological Laboratory, New York. With a Diploma under your wing, your career will soar to new heights. You will officially hold the title Kalypso TwistZ Certified Gemologist making you an expert on Kalypso TwistZ Jewelry. We encourage you to then use your title on your business cards, s, Facebook profile and every other place where you deem fit. We also encourage you to frame your Diploma and display it with pride. You could carry it to Jewelry Therapy Sessions and display it in a place of prominence. Congratulations! You are on your way to becoming a Kalypso TwistZ Certified Gemologist! BIRTH OF A STAR! A gemstone or a gem is the heart and the soul of any piece of jewelry! Because gemstones come in many different colors and feels, they make a piece of jewelry into a work of art! They are naturally occurring minerals which are cut and polished and set in jewelry simply because of their beauty. A gem takes you to a realm beyond thought to a world filled with beauty and intrigue! Gemstone Classification: Gemstones can be broadly classified into 2 categories: precious and semi-precious stones. Precious Gemstones are Diamonds, Rubies, Sapphires and Emeralds. All other gemstones are considered semi-precious. This distinction is broadly based on rarity and commercial value of the gemstones. However, this deceptively simple classification can be misleading. Sometimes a semi precious gemstone costs more than a precious gemstone, but those times are rare and far between.

2 Gemstones are primarily classified by their color, clarity and hardness. Many gemstones are heat treated to enhance their natural colors and luster. FYI> Mohs Scale of Mineral Hardness: Created in 1812 by German Gemologist Friedrich Mohs, this scale compares hardness and scratch resistance of various minerals when compared to other minerals. It is based on the observation that one natural mineral will scratch another. Talc being 1 on the scale of Absolute Hardness and Diamond being 10. Other fun examples: graphite (pencil lead) is a 1.5; Finger nails are 2.2, a normal knife blade is a 5.5. We refer to this scale to note the hardness of the gems we use. Some gems, like opals, though beautiful are impractical for daily wear. On the Mohs Scale, they are a 4 in hardness. This would mean that they are easy to chip and damage if they come in contact with another material. If you own an opal, wear it rarely! In Kalypso TwistZ, our jewelry and gemologists refer to the Mohs scale before using new gemstones. Our jewelry is meant to give you lifelong wearing pleasure! IDENTIFICATION: The Family Tree! The first characteristic a Gemologist uses to identify a gemstone is its CHEMICAL COMPOSITION. This is done by identifying the basic natural elements that make up the gemstone. For example, a diamond is primarily made up of Carbon. Some gemstones are complex compounds of many elements. A great majority of gems are oxides (they contain oxygen as one of their elements) or silicates (they contain sand or silicon) and are formed as crystals during the cooling of the Earth s crust over the past millennia. For further analysis, we look at their molecular structure. Many gems are crystalline in their atomic structure and are therefore classified by their structure. They maybe Cubic, Hexagonal, Tetragonal, Orthorhombic, Monoclinic or Triclinic Gemstones are classified into different groups, species, and varieties. For example, Ruby is the red variety of the species corundum while any other color of corundum is considered a Sapphire! A Ruby and a Sapphire have the same chemical composition. Both are from the Corundum family yet exhibit different colors. Even the same gemstone can occur in many different colors, Sapphires, for example, occur in many shades of pink, white, blue and orange! This difference in color is based on the atomic structure of the stone. Although different, these families have almost the same chemical composition. They are however, not exact. Every now and then, an atom is replaced by a completely different atom (and this could be as few as one in a million atoms). These so called impurities are sufficient to absorb certain colors and leave the other colors unaffected! FYI> After examining the color of a gemstone, an expert Gemologist can tell you, with a fair amount of accuracy, which country the gemstone was mined in! This is especially true for Emeralds and Blue Sapphires.

3 Through detailed understanding of this natural phenomenon, scientists developed treatments to use impurities to manipulate the color of a gem. We will discuss this effect more in detail later. Gems are further characterized by the following: Optical Characteristics Optical Character Refractive Index Dispersion Specific Gravity Hardness. Delving into these details is not the scope of this course. FYI> Our Gemologists and Designers focus on optical characteristics of gemstones in great details. Color, Hues and brilliance, which are optical characteristics, make gemstones beautiful. We will discuss Color and Brilliance in greater detail later in Color & Cut! Now for a shocking truth! There is no universally accepted grading system for gemstones. Historically, all gemstones have been graded using the naked eye. Gemological Institute of America included a major innovation only recently: the introduction of 10x magnification as the standard for grading clarity especially of Diamonds. Most other colored gemstones are still graded using the naked eye (assuming 20/20 vision). Pedigree A good way of understanding basic gradation of Gemstones can be learned easily if we focus on 4 Cs of Gem Valuation. The 4 Cs are Color, Cut, Clarity and Carat Weight. COLOR: Probably the most visible quality of a gemstone is its color. It is the defining trait of a gemstone. Hue, Striation, Feel are equally important when describing the tonality of the color. A consistent color is more desirable than color variations within a gemstone. Rich tonality coupled with a precise CUT gives a gemstone life and fire, qualities that are prized. Color Zoning is the uneven distribution of coloring within a gem. A good designer can make use of color zoning to his advantage by creating a one-of-a-kind look. For the most part, even, rich colors are more sought after. CUT:

4 When a gemstone is mined, it is washed with water or other solvents to clean soil and other natural material. It is in a rough crystalline form appropriately called rough. After studying the rough ore-crystal, an expert gem cutter brutes the ore into smaller crystals. Each crystal then goes through an assortment of precise cutting and grinding steps. He is very much like an expert sculptor creating a masterpiece! His job is to enhance the natural beauty, color and luster of the gemstone. Popular gemstone shapes are Round cut Marquis cut Oval cut Cushion cut (square with rounded off edges) Princess cut (square) Emerald cut (rectangular) and Pear shaped or Tear Drop cut. Polishing & Finishing The last and final stage of cutting a gemstone is Polishing and is arguably the most important step. Finishing involves grinding, tumbling (depending on the gemstone), and polishing. In Kalypso TwistZ, we use gemstones that are opaque & translucent. It is important to understand their optical characteristics because they determine the cut. Opaque gemstones such as Black Onyx, Agate etc. are commonly cut as cabochons. Gemstones cut smooth & dome shaped are called cabochons. Opaque gems normally have a beautiful intricate surface. These gems are used in Jewelry Settings to exploit their surface beauty. Grinding wheels and tumbling bins are used to smoothen and shine the surface of the gemstone. Gems which are translucent, like topaz, quartz and corundum, are normally faceted. Faceting is a method of cutting a gemstone with mathematical precision to maximize the gem s Optical Characteristic. Facets are cut at proper angles allowing maximum reflection and refraction of light making the gem brilliant. Cabochon as well as Faceted gemstones can also bear a beautiful Checker board cut. This is a technique where the gemstone is cut into many precise square facets spaced at regular intervals around the stone s table giving it a 'Checkerboard' effect of light and dark squares. This creates very interesting patterns of brilliance and life when the gem is moved in light. FYI> as you can see, the term CUT is very deceptive. In Gemology, it refers to the shape as well as the finish of the gem and often is a very important determinant of its selling price! FYI> gem diagram..

5 CLARITY: Clarity is expressed in terms of the absence of natural serrations, blemishes, abrasions within the gemstone as is visible to the naked eye. The clearer the gemstone, the more the value. Blemishes within a gemstone are called inclusions. An inclusion is any type of material that is not part of the original mineral. Inclusions are solid, liquid or gaseous presence of foreign material within a gemstone. Clarity Based Grading: Gemologists use the following grading system that was designed by GIA and is primarily used for Diamonds. IF-FL: Internally Flawless, Totally clear under a 10x Magnification VVS1-VVS2: Very, Very Small Inclusions under a 10x Magnification VS1-VS2: Very Small Inclusions under a 10x Magnification SI1-SI2-SI3: Small Inclusions under 10x Magnification I1-I2-I3: Imperfect: Inclusions visible to the naked eye. For colored gemstones, the scale is as follows: Type I colored stones include stones with very little or no inclusions. They include Aquamarine, Topaz and Zircon, among others. Type II colored stones include stones that often have a few inclusions. They include Corundum, Garnets and Spinel, among others. Type III colored stones include stones that usually always have inclusions. Stones in this category include Emeralds, Tourmaline, etc. Carat Weight: The selling price of a Gemstone is easy to understand when it is related to the total weight of the gemstone. The unit of measurement for gemstones is carats. To those of you who want more precision, 1 carat (or ct. for short) is approx. 200 milligrams or 0.2 grams. Prices of gemstones are expressed on a per carat basis. It is also important to note that a rough gemstone is much larger in carat weight before it is cut. Usually through the cutting process, lots of lower quality material is removed, especially inclusions when possible. The result is less mass, but usually a much prettier and higher quality gemstone. FYI> The term karat kt. for short and carat are both commonly used terms in our Jewelry world. Karat is usually used to describe the purity of a metal (like Gold) and carat is used to denote the weight of a gemstone! Kalypso TwistZ Gemstones:

6 Let s now take a closer look at the gemstone we use in our collection. Our collection is always growing, so please keep updating your knowledge! What is Quartz and Topaz? Quartz and Topaz are minerals that are found in abundance. Because of their beauty and that they can be manipulated into many vibrant colors, they are widely used in Jewelry. They are often substituted as each other. For example, Smoky Topaz is really Smoky Quartz! They are basically silicates and have a chemical structure very similar to glass. Quartz is basically Silicon and Oxygen. Topaz has Aluminum, Hydrogen and Fluorine molecules in its atomic mix along with Silicon and Oxygen. Quartz is 7 on the Mohs scale while Topaz is 8. Mined Quartz and Topaz are colorless with many internal striations. Through various heat treatments, which we will go through later in the course, they are permanently transformed to rich, vibrant colors. Drusy Agate: Drusy Agate in chemical composition is exactly similar to Blue Agate. It consists of a sparkling layer of very tiny quartz crystals coating the surface of the Agate. To be considered gem quality, Drusy crystals cannot be too coarse or large and must be in near-pristine condition. Each Drusy piece is unique! Once damaged, the crystals cannot be repaired. Many Drusy Agates are colored to make them attractive and available in many colors. Currently we use Black Onyx and Golden Sand Stone. Spas for Gemstone! Various Treatments to look their best! To look better, natural gemstones go through a myriad of spa treatments! They go through heat treatment, waxing, Oiling, and Fracture filling. Treatments are done to enhance natural color or to burn off impurities within a gemstone. Depending on the type and extent of treatment, they can affect the value of the stone. Some treatments are used widely because the resulting gem is stable. Such treatments do not decrease the value of a gemstone, while others are not accepted commonly because the gem color is unstable and may revert to the original tone. Such treatments reduce the value of gems dramatically. For example, fracturefilled diamonds are a fraction of the cost of real diamonds as the treatment is not permanent. All gemstones used in Kalypso TwistZ are treated to enhance natural colors and the colors are permanent.

7 Treatment #1: HEAT: Heat can improve gemstone color or clarity. The heating process has been well known to gem miners and cutters for centuries, and in many gemstones heating is a common practice. For example, most Citrine is made by heating amethyst! Most Sapphires and Rubies (the family is Corundum) are heat-treated to improve both color and clarity. Both shades of Blue Topaz, lighter and darker London Blue shades, have been heat-treated to change the color from white to blue. Green Quartz also goes through a heat-treatment to achieve the yellow-green color. Treatment #2: Waxing and Oiling Some gemstones like Emeralds contain natural fissures on their surface. These get filled with a wax or oil to make the surface appear consistent. The wax or oil is colored to make the emerald appear richer as well as clearer. This treatment is considered temporary as the wax and oil dry out in time Treatment # 3: Fracture filling Some gemstones have deep fissures running through them. They start at the surface and go through the entire gemstone making the gem brittle. Fracture filling has been used with gemstones like diamonds. A pressurized colorless gel is inserted into natural fissures in a diamond. The gel acts like a sealant thereby strengthening the diamond without distorting its beauty. This treatment is temporary and the gel leaks out over time. Plastic Surgery! Lab-created Gemstones are not imitations. All precious gems like diamonds, emeralds, rubies, and sapphires have been manufactured in laboratories. They possess identical chemical and physical characteristics to the naturally occurring gemstones and are impossible to differentiate. Lab created corundum including Rubies and Sapphires are used extensively in our Jewelry World. Whether a gemstone is a natural stone or a lab-created, it is very important to remember the physical and chemical characteristics of both gems are the same. Lab-created gemstones tend to have a more vivid color and a more appealing look than their real counter parts. FYI> So, as a gemologist, how can you broadly tell the difference between a lab created gem and a mined gem? Here is a clue... Read the part about Inclusions again! Remember inclusions

8 are natural impurities occurring in a crystal? They cannot be introduced in labs! So look for blemishes, and scars within the gem and you can bet it is real! Body Doubles! Artificial Gemstones Some gemstones are manufactured to imitate other gemstones using man made materials like polymers. A good example are Cubic Zirconia or CZs for short. They are manufactured in factories and are meant to resemble Diamonds. They cost a fraction of a real diamond. Imitation or artificial gemstones are fashioned to copy the look and color of real stone but possess neither their chemical nor physical characteristics. Often, some artificial gemstones look better than their real counterparts. In Kalypso TwistZ, we use the finest Cubic Zirconia ever made. It is featured in the Spectra II Xpression. It is fabricated with such precision that you see a starburst on one side made up of 8 perfect arrows and a pattern of 8 hearts when seen for the other side. It is a PERFECTLY CUT crystal giving you unbelievable brilliance! Crystals: Lead crystal is made from glass that has been treated with lead oxide. They may be hand cut or faceted making them look like a gemstone. With the addition of lead, the glass gets a higher refractive index creating an attractive sparkling effect that mimics a gemstone. Glass Crystal can also be colored and shaped and are used to make good looking yet inexpensive jewelry. The most recognized crystal is the luxury brand of Swarovski. We use Swarovski crystal in some of our designs. They are famous worldwide for their precision cuts, clarity, and sparkle. Not only are their cuts distinct, but the assorted colors and shapes cover a broad spectrum in Jewelry design. The brilliant sparkle of each crystal is actually resulted from a glass composition containing 32 percent lead. Besides this refraction maximizing strategy, special metallic coatings are used on some of the crystals to ensure that light refracts from the surface in a rainbow spectrum. One of the most utilized coatings is Aurora Borealis, simply known as "AB." Jewelry Settings: a crash course in Metallurgy A precious metal is a rare, naturally occurring metallic element of high commercial value. Chemically, the precious metals are less reactive than most other elements and are referred to as Noble Metals. Royal Family Traits: Some common chemical and physical features are: 1- High Luster: that makes them naturally shiny and can be polished to a mint finish 2- Malleable: meaning they are capable of being made into different shapes like bangles, rings etc.

9 3- Ductile: they can be drawn into wires without losing their inherent strength which means they can be made into bracelets and chains! 4- Have higher melting point than other metals. 5- They are resistant to corrosion and oxidation Historically, precious metals have always been used as currency. Because of their perceived value, they have always commanded higher prices than other metals. The best-known precious metals used in Jewelry are Gold, Silver, Platinum and Palladium. Other precious metals like Rhodium and Iridium are used as plating agents which we will discuss later. Platinum used in jewelry is used at 99.99% purity. It is one of the rarest metals in the world. It is said that all the Platinum in the world would fit an average sized living room! Platinum is the most expensive precious metal. As a pure metal, platinum is silvery-white, lustrous, ductile, and malleable. Platinum is also hypo-allergenic! Gold: Gold is a soft, lustrous, malleable and ductile metal. It is one of the least reactive solid chemical elements. The metal therefore occurs often in nature as nuggets or grains in rocks, in veins or alluvial deposits on Earth. FYI> Nitric Acid dissolves silver and other base metals but is inert to Gold. This property has long been used by Jewelers to confirm the of gold in items, giving rise to the term acid test! Gold is a very soft metal. It needs to be blended (or Alloyed) with other metals. Pure Gold is known as 24 karat purity or 24 kt in our industry. When alloyed with other base metals, we can change the hardness, ductility, melting point, and color of Gold making it suitable for jewelry. For example, 18kt gold contains 75% Gold & 25% copper. 14kt Gold contains 57% Gold with the balance being Brass. White gold alloys can be made with Palladium or Nickel. For example, 18kt white Gold contains 17.3% nickel, 5.5% zinc and 2.2% copper and is silvery white in appearance. However, many people are allergic to Nickel and therefore Palladium, though more expensive, is used. Silver: Silver is a ductile, malleable metal with a brilliant white metallic luster that can take a high degree of polish. It has the highest electrical conductivity of all metals! We use Sterling Silver in all of our Jewelry in Kalypso TwistZ. Sterling Silver is an alloy of Silver containing 92.5% and 7.5% copper, hence Sterling Silver is also known as 925 Silver. It is the finest silver that can be used in Jewelry. Silver of 99.9% purity is too malleable and is therefore not used in its pure form. We use Rhodium, which is another precious metal, to plate final pieces of Jewelry to give them an absolutely beautiful mirror finish. Other metals used in Jewelry range from Bronze to Stainless Steel. These metals are plated with one of the precious metals to make them look jewelry worthy. However, they cannot be sized

10 and altered once they are finished. Plating lasts anywhere from a few months to a few years. Therefore, jewelry that endures the abuse of time is made with precious metals. Polish & Finish When a piece of jewelry comes into the Polishing room, it looks terrible! The metal has gone through immense trauma of very high temperatures, sharp instruments that define its various features and very strong chemicals that are used in manufacturing. The object of polishing a piece of jewelry is to get the metal to a high polish or a satin sheen. There are three generally used terms in our industry that are often used interchangeably. They are: Deburring Deburring is the removal of all sharp edges, air bubbles and burrs on a piece before gem setting. Polishing Polishing is the use of abrasives in a decreasing order of coarseness to get a smooth, even surface. Buffing Buffing is done by a set of hard to soft buffing wheels to get a smooth, bright, high luster final finish. FYI> Usually the metal is completely finished before the gemstone is mounted! The final hurrah is the Plating room. As discussed before, we use Rhodium in Kalypso TwistZ to give our jewelry the mint finish that is so well loved! In an electro-plating bath, a strip of Rhodium is placed at one terminal and our jewelry is placed at the other. Once the electrical current is turned on, molecules from the Rhodium spread evenly on the surface of the sterling silver. The result is spectacular! Rhodium plating is done after the gemstones have been set. This is the final step in a long and intricate process. Now a piece of jewelry is said to be finished and ready to adorn its proud new owner! FYI> Rhodium is the rarest metal on earth. Its annual production is only3 tons per year. Rhodium Plating increases the wear ability of jewelry and prevents abrasion. Though plating wears off, it can be repeated many times without affecting the jewelry

OUR MATERIALS Platinum

OUR MATERIALS Platinum Platinum is a natural white metal that has increased in popularity over the last few years. Although it is not as reflective as silver or white gold, it does not fade or tarnish,