Do you have a favorite shirt and don’t want to throw into the garbage ‘coz you wore it when you hand your first kiss? Or you wore it when you caught your boyfriend cheating on you and it will serve as a reminder that you will not fall in love again with same kind of good-looking and egocentric guy.
The good news! Here are the 7 ways to give it a second chance (not the guy but the T-shirt).
1. A tee that’s too small or faded to wear on its own makes a great layering piece. Thinner tees or camisoles can look so stylish when you pile one on top of another. Choose two shirts in coordinating colors and let the first layer peek out at the bottom.
2. Cut off the sleeves and make it a cute tank top. Give it a slightly military look sewing patches on the front and bunching the shoulders together and securing them with a gold or silver chain from the crafts store.
3. Change the color! Channel your inner hippie and break out the tie-dye. Or just dye it a few shades darker. This works even with old concert tees, or anything with writing on it.
4. Sew buttons of various sizes along the neckline for a necklace effect. Pick out buttons in coordinating colors or fun shapes, or for a slightly dressier look, try metal buttons with a silver or gold finish.
5. Take a T-shirt that’s slightly baggy at the waistline and cut four 2-inch vertical slits in the front and in the back, lace it with a ribbon and tie it as a belt.
6. Cut some small slits or holes into a shirt that can be layered over another tee or a tank top, letting the color of the undershirt show through a bit.
7. Try tracing a favorite design onto an old white T-shirt as a fun art project. (What’s the worst that could happen? You’d throw it away, which you were about to do anyway!) With computer transfer paper (available at the office-supply stores), you can print out your own pictures or sayings. You could even print out an inside joke that only a few friends know, and watch them crack up when they see you wearing it.
Pearls, lustrous concretion produced by certain bivalve mollusks and valued as a gem. Pearls consist almost entirely of nacre, which is the substance forming the inner layers of the mollusk shells. Nacre, known as mother-of-pearl, is composed primarily of aragonite crystals. The pearl is an abnormal growth resulting from the invasion of the body of the mollusk by a minute irritant, such as a parasite. The particle acts as an irritant in the mollusk and becomes coated with layer upon layer of nacreous material. Both marine and freshwater mollusks produce pearls, but the most valuable varieties originate in the pearl oyster of the Persian Gulf.
The most highly prized pearls are spherical. When a pearl that has been cut from the shell presents a hemispherical surface, it is sometimes called a bouton pearl. If a solid pearl has an irregular shape, having grown over a rough object, it is known as a baroque pearl. In the jewelry trade, pearls are commonly known as pear, bell, or drop, according to the shape. Pearl coloration varies widely, the most prized shades being white, black, rose, and cream.
One of the important marine-pearl fisheries on the North American continent is off Baja California, Mexico, the central point being at La Paz. Other fisheries are located in the Gulf of Panama, in the West Indies and the islands of the South Pacific, and along the coasts of India, the Persian Gulf, Japan, Mexico, and western Central America, especially in the Pearl Cays, near the coast of Nicaragua. In Australian waters pearls are fished on the coast of Western Australia and of Queensland and in Torres Strait.
River pearls are produced by freshwater mussels in various parts of the world. China is the principal trader in river pearls.
Natural, spherical pearls have been cultured successfully since 1920. In this process a mother-of-pearl bead, from three-quarters to nine-tenths of the diameter of the desired product, is introduced into the pearl oyster. Over a period of years the oyster deposits layers of nacre around the bead. Cultured pearls are not easily distinguished from genuine pearls except by an expert. The technique of producing spherical cultured pearls was developed in Japan, and the culturing of pearls is a major Japanese industry. Artificial pearls, in contrast to cultured pearls, are entirely artificial, made largely of glass.
SKIPPY TAN
Skippy to her friends, Annie is supermom these days to two adorable, rambunctious boys, Gregory and Gabriel.
The demands of motherhood start at 6:15 am with a much-need shot of coffee, then to get the kids up and start breakfast. It ends when she gets the kids to bed at 8:45pm. In between, she manages an almost daily aerobic session at the Y, a half an hour to catch up on email and, if she is lucky, another half an hour to catch up on the latest bestseller.
Our Annie is a very, very busy, typical mom!Those of us in the know, of course, are in awe with her sense of purpose. Not so very long ago, our Annie was in the thick of corporate life. Her career began in the Oil Industry in Singapore, in Employee Relations, and the banking industry in the Philippines. This career went on a temporary pause when she started (and completed) her MBA in the prestigious Asian Institute of Management.
She eventually found a very comfortable niche in the retail industry in Hong Kong. She was General Manager for the company that represented the European brand of the “United Colors of Benetton”, and later, became Director of Operations for a consortium of duty free stores across Asia while she was based in Hong Kong. Motherhood is the culmination of life’s adventures, its reward and its most meaningful chapter.
Here’s more about Annie:
Also known as: Skippy, Patricia Ann Yu, Mrs. Tan, Mom
Astrological Sign: Sagittarius
Zodiac Year: Rabbit
Relationship Status: MARRIED
Activities: Aerobic exercise, confessed “foodie”
Interests: Reading, shopping, food sampling (whenever she gets as chance)
Favorite TV Shows: CSI series, ER, Grey’s Anatomy (whenever she gets a chance) Favorite Movies: The Last Emperor
Favorite Music: Enya, Van Halen, Santana, Huey Lewis, Zucherro
Favorite Books: mystery thrillers
Favorite Quotes: “The end does justify the means”
Education gadget: TIVO
Favorite Samantha Rose piece: Annie is a classical girl, she goes for white or colored individually hand-knotted strands such as NS012WRg. But we can totally see her with our peach pearl pendant in rhodium plated sterling silver (PS0070).
Annie has proven that she is perfectly comfortable negotiating across the conference table as well as preparing her family’s meals on the kitchen table … but when asked which would give her more satisfaction … “being wife and mother, of course!”Samantha Rose Exclusive Jewelry Designs
http://www.samantharose.us
SamanthaRose.us is a trusted American company that brings together fresh, inspired jewelry products and designs from around the world. Samantha Rose is dedicated to provide the high quality fine exclusive pearl jewelry for everyone.
Samantha Rose features the best selling exclusively designed and celebrity inspired pearl jewelries. They sell pearl jewelry like necklace, earrings, bracelets, wedding accessories, and custom-made pearl jewelry pieces.
Diamond, mineral form of the element carbon, valued as a precious stone. Diamond is the hardest natural mineral and has many other exceptional properties that collectively make it an important industrial and scientific material. Unique geologically, diamonds form at great depths within Earth and are typically billions of years old.
HOW DIAMONDS FORM
Diamonds are crystals composed of pure carbon. In nature, diamond crystallizes from hot carbon-rich fluids. This crystallization requires tremendous heat and pressure—1000 to 1200°C (1800 to 2200°F) of heat and 50 kilobars of pressure. (One bar is based on the pressure the atmosphere exerts at sea level, about 1.02 kg per sq cm, or 14.7 lb per sq in; 50 kilobars is 50,000 bars.) The pressures and temperatures at which natural diamond forms only occur deep underground. Scientists believe that diamonds form at depths greater than 150 km (93 mi), and there is evidence that some diamonds formed as deep as 670 km (420 mi) beneath Earth’s surface.
Concentrations of diamonds great enough to be economically feasible for mining are usually found in Earth’s oldest continental regions, called cratons. Cratons form the cores of most continents and consist of inactive geological areas more than 2 billion years old with thick crust and deep roots extending into the mantle beneath. Craton conditions are ideal for diamond formation and preservation. Scientists have determined the ages of some diamonds by dating mineral impurities trapped within the diamonds. These data reveal that most cratonic diamonds are ancient, some older than 3 billion years.
Much younger volcanic rocks—kimberlites and lamproites—pass through the cratonic rocks in a liquid form called magma during their rapid ascent to Earth’s surface. These flowing veins of rock act as carriers of diamonds and other rock fragments. After eruption they solidify, forming funnel-shaped kimberlite “pipes.” These pipes are primary diamond deposits. Many diamonds are recovered at a distance from their primary deposits in secondary alluvial deposits, which are loose eroded materials left behind by flowing water. In some instances diamonds are also found in sandstones, conglomerates, and other sedimentary rocks that presumably solidified from former alluvial deposits. Wind and glaciers can also transport diamonds from their point of origin at Earth’s surface.
Small, generally low quality diamonds form in rocks at shallower depths under pressure conditions that are higher than usual for those depths. Tectonic movement, rather than magma, transports these diamonds to Earth’s surface. Deposits of this type occur in areas such as Kazakhstan and typically involve the collision of a continental and an oceanic plate followed by rapid uplift of deeply buried rocks. Diamond deposits brought to the surface by tectonic movement are generally younger than kimberlitic diamonds, and typically consist of microdiamonds (less than 1 mm across) or graphite relics of larger diamonds.
Diamonds are also found in meteorites and near meteorite craters on Earth’s surface. Extremely small diamonds (nanodiamonds) occur in many types of meteorites and have a lower density than other diamonds. Meteorites can also produce pressure and heat at the moment of impact sufficient to transform carbon into diamond. Diamond found in a type of meteorite called ureilite is thought to form directly from graphite contained in the meteorites upon impact. Impact-crater diamonds are opaque and range from very small to around a centimeter in diameter.
DIAMOND PROPERTIES
Diamond is the hardest natural substance known. This hardness is exhibited in diamond’s resistance to scratching and its ability to scratch other materials. Steel and glass, for instance, can be scratched by diamond. The Mohs hardness scale, devised by the German mineralogist Friedrich Mohs to indicate relative hardness of substances on a rating scale from 1 to 10, assigns diamond a value of 10. Diamond’s hardness is not a constant quantity but varies even within a single diamond.
Diamonds are crystals composed of carbon atoms. Atoms in a crystal are arrayed in a regular repeating pattern. A crystal’s outward form, bounded by smooth plane surfaces that meet at predictable angles, reflects this internal order. Crystals tend to cleave, or split, along lines called cleavage planes between layers of atoms. In the case of diamond crystals, each carbon atom is bonded to four surrounding carbon atoms. This microscopic arrangement determines the visible shape of diamond crystals, which are generally octahedrons (solid shapes with eight faces). Individual diamond crystals therefore cleave cleanly along planes parallel to the faces of an octahedron.
Two important properties, brilliance and fire, contribute to diamond’s beauty. Brilliance is the fraction of the light that falls on a diamond that the diamond returns to the eyes of an observer—the more light returned, the higher the brilliance. Diamond’s brilliance arises from its index of refraction, which determines the angle at which light is bent as it crosses the boundary between the air and the stone. Fire is the ability of a substance to split white light into rainbow colors—the greater the separation between colors, the greater the fire. Diamond’s fire originates with its dispersion, which is the difference in diamond’s index of refraction for light of different colors. Diamond has both a higher index of refraction and a higher dispersion value than any other natural, transparent, colorless material.
Diamonds exhibit a wide range of transparency and color. Transparency is a measure of the amount of light that passes through a diamond rather than being absorbed. Colorless diamonds, known as white diamonds, are most familiar, but green, blue, red, orange, yellow, and brown diamonds also are known. Structural imperfections or dislocations and the presence of trace elements, mainly nitrogen, cause color in diamonds. Some diamonds luminesce (emit light) when exposed to sunlight or other ultraviolet-light sources. The light the diamonds emit is usually light blue, but yellow, orange, and red luminescence occurs in some stones.
Most diamonds used as gems are single crystals large enough to be easily visible to the eye. Diamond also occurs, however, in polycrystalline forms commonly known as ballas, bort, and carbonado. Ballas is a compact, spherical mass of tiny diamond crystals of great hardness and toughness. Bort is an extremely hard, dark, imperfectly crystallized diamond. The term bort sometimes is also applied to minute fragments of gem diamonds. Carbonado is an opaque grayish or black form of diamond that consists of microscopic crystals and has no cleavage. Ballas, bort, and carbonado are all used industrially, in lapidary (gem-cutting) work, and as a tough coating for the tips of drills and the edges of cutting tools.
Other characteristics of diamonds are frequently useful in identifying the stones and in differentiating between true diamonds and imitations. Because diamonds are excellent conductors of heat, they are cold to the touch and are sometimes called “ice.” Most diamonds do not conduct electricity well, but diamonds do become charged with positive static electricity when rubbed. Diamond resists attack by acids or bases. Since diamonds are a form of carbon, like coal, they will burn, but only when heated to extremely high temperatures.
The density of diamond ranges between 3.15 and 3.53 g/cm3, but the density of pure diamond is always very close to 3.52 g/cm3. Diamond is much denser than crystals composed of elements of similar weight to carbon atoms because the carbon atoms in diamond are packed tightly together. Quartz, for example, is composed of atoms of silicon and oxygen, both of which are heavier than carbon atoms. The density of quartz, however, is only 2.65 g/cm3.
DIAMOND CUTTING
Rough diamonds are not brilliant and can appear greasy. Diamond cutting encompasses a number of processes that bring out the beauty of gem diamonds. These processes include cleaving, sawing or laser cutting, and polishing. A diamond cutter seeks to enhance the brilliance and fire of each stone and to eliminate imperfections, such as cracks and cloudiness. The cutter develops a plan that will accomplish these goals while still producing a gem of the greatest size and hence maximum value. About half of a natural diamond’s size is lost in diamond cutting.
Examining the stone is the first step in diamond cutting. The cutter determines where cleavage planes lie and decides how the stone can best be divided by cleaving and sawing. Ink marks on the rough diamond serve as a guide for the shaping to follow.
The cutter next places the diamond firmly in a holder for cleaving. A light blow of a hammer on the cleaving iron, which is held against the diamond parallel to the cleavage plane, cleaves the stone. In present-day practice cutters more often saw diamonds or cut them with a laser rather than cleave them. The saw is a thin metal disk, the edge of which is impregnated with a mixture of diamond dust and oil.
Polishing, the final step in the cutting of a diamond, consists of forming the facets of the finished stone. Cutters most often choose the “brilliant” form, which has 58 facets. During the polishing process a mount called a dop firmly holds the gem. A flat, horizontally revolving cast-iron wheel coated with a mixture of diamond dust and oil forms the facets. The cutter holds the stone in its dop against the surface of the wheel until the facet forms. In the course of polishing, the cutter moves the stone many times in its dop to present new surfaces for polishing. See also Gemstones.
JUDGING A DIAMOND’S QUALITY
Only high-quality diamonds are suitable for use as gems. In judging the quality (and therefore the value) of a cut diamond, a buyer must take into account four criteria, known as the “four C’s”: color, clarity, carat weight, and cut. Colorless stones are extremely valuable, while yellow or brown-tinged stones are regarded as imperfect. Fancy, colored diamonds, or fancies, exhibit clear, strong colors such as blue, green, red, and orange. Fancies are quite rare and highly prized. The presence or absence of internal blemishes and flaws determines clarity. Weight reflects a diamond’s size. The unit of weight usually employed for diamonds and other gems is the metric carat, which is equal to 0.2 g (about 0.007 oz). Another unit used to express the weight of diamonds is the point, equal to 0.01 carat. A stone of 82 points would therefore weigh 0.82 carat. A 5-carat stone is worth more than five 1-carat stones that are otherwise of the same quality. The final criteria buyers use in determining the quality of a diamond is its cut. The cut is the shape and proportion of the stone, as determined during the diamond-cutting procedure.
SYNTHETIC AND IMITATION DIAMOND
High demand for diamonds has led to the development of methods for producing artificial diamonds. Artificial diamonds used in industry are generally known as synthetic diamonds; artificial diamonds used for ornamentation are called imitation diamonds. Even though the majority of natural diamonds are industrial grade, only about 10 percent of the diamonds used for industrial purposes are natural diamonds. The other 90 percent are synthetic. The two most common processes of synthesizing diamond are the high-temperature high-pressure (HTHP) and chemical vapor deposition (CVD) methods. The HTHP method converts carbon to diamond at high temperature and pressure using a molten metal catalyst. The HTHP method is sometimes also used to change or enhance the colors of some rare natural diamonds, thus making them more valuable on the market. The CVD method produces diamond coatings by heating a hydrocarbon gas over a metal surface. These diamond coatings greatly extend the lifetimes of precision dies, drills, and saw blades.
The high price of gem diamonds has created a market for imitation diamonds made from less expensive materials. Minerals that strongly disperse light, including cubic zirconia, transparent quartz (rock crystal), synthetic rutile, corundum, spinel, and moissanite (silicon carbide), are all used as imitation diamonds. Other imitations are made from a lead glass known as paste or strass. Devices called thermal conductivity probes can detect imitation diamonds because imitation diamonds generally do not conduct heat as well as real diamonds. Imitation diamonds can also be identified optically and are easily scratched by real diamond.
FAMOUS DIAMONDS
A number of individual diamonds have become famous, primarily for their great size but also for their exceptional color, cut, uniqueness, or history. The Great Mogul diamond, reputed to have weighed 240 carats when cut, has disappeared since it was described by the French traveler Jean Baptiste Tavernier in India in 1665. Some authorities believe that the Koh-i-noor diamond, which now weighs 106.1 carats and is one of the British crown jewels, was part of the Great Mogul. Jean Baptiste Tavernier is also associated with the Hope diamond, a 45.52-carat blue diamond that originally weighed 110.5 carats. The Hope diamond is a recut version of the Great Blue diamond. The Great Blue diamond was once part of the French crown jewels.
The Cullinan, the largest rough diamond ever found, was discovered in the Premier Mine in South Africa in 1905. The government of the Transvaal, a British crown colony that later became part of the Union of South Africa, presented the Cullinan to King Edward VII. The Cullinan weighed 3,106 carats (1.37 lb) before cutting and was pronounced by crystallographers to be a cleavage fragment of a considerably larger stone. When the stone was cut a total of 105 gems were produced weighing 1,063 carats in all. The largest of these was a 530.2-carat drop-shaped stone called the Star of Africa or Cullinan I. The Star of Africa is the second largest cut diamond in existence and is set in the British royal scepter. The largest known cut diamond is a yellowish-brown stone called the Golden Jubilee. It was given to the King of Thailand in 1997 to honor the 50th anniversary of his coronation.
The Vargas diamond, found in Brazil in 1938, weighed 726.6 carats in its uncut state. When cut in 1945, it yielded 29 stones with a total weight of 411 carats. In 1934 a diamond of almost precisely the same weight, the Jonker diamond, was discovered in an alluvial deposit near the Premier Mine. The Jonker is the finest-quality large diamond ever found. It was cut into 12 gems ranging from 125.4 to 5.3 carats in weight. In 1967 the Lesotho diamond was discovered, also in South Africa. It weighed 601.3 carats uncut. Other famous diamonds include the Regent, the Sancy, the Tiffany, the Orlov, and the Dresden Green.
1. Begin the Dutch Spiral Beadwork Stitch by threading a #12 beading needle with about 4 or 5 yards of thread, depending upon your thread length preference. Nymo works well.
2. Add 6 beads in this order: 1 size 8/0, 1 size 14/0, 1 size 8/0, 1 size 14/0, 1 size 8/0, 1 size 14/0.
3. Tie this into a circle, and leave a tail of about 10 inches. This tail will be used for adding your clasp or findings.
4. Start the next row by passing the needle through the first Size 8/0 bead you strung.
5. Pick up 2 Size 11/0 beads and 1 size 8/0 bead.
6. Pass the needle through the next size 8/0 bead from the previous row.
7. Continue adding 2 size 14/0 and 1 size 11/0 until you finish the row. Each row has 3 sets of 3 beads each.
8. For the third row, add 3 size 11/0 and one size 8/0, then pass through the first size 8/0 bead from the previous row. [an 11/0, a 14/0 and an 11/0.]
9. Continue in this count until your chain reaches the desired length.
10. To decrease at the end, reduce the size 11/0 added to 2 for one row, and then to 1 for one row.
11. Use the remaining thread to add your clasp or findings. Add a clasp at the other end, too, using the tail that was originally left.
Tips:
The term artificial gem is used to describe either an imitation of a natural gemstone or a synthetic gem that is chemically identical to naturally occurring gems.
Imitation Gem
Such a gem may be made of flint glass, often silvered on the back to increase the brilliance. Since World War II, colored plastics have replaced glass, especially in costume jewelry. Plastics are cheaper, more easily molded, and lighter in weight.
During the 19th century, artificial pearls were made by blowing hollow beads of glass and pouring into them a mixture of liquid ammonia and the white matter from the scales of fish such as the bleak, roach, or dace. A much better type of artificial pearl, the indestructible bead, was introduced shortly after 1900. The bead is made of solid glass with only a narrow hole for the thread. Pearl essence, consisting of the crushed scales of certain herring, is applied to the outside of the glass and covered with a transparent, colorless lacquer.
The most successful imitation of a diamond is strontium titanate, made by a flame-fusion technique. Its index of refraction is almost identical to that of a diamond, and it has a higher dispersion. Thus, it has the brilliance and greater fire than the diamond. It scratches easily, however. A harder material simulating the diamond is rutile, or titanium oxide.
Synthetic Gems
The term is limited by the U.S. Federal Trade Commission to manufactured materials that duplicate a natural gemstone chemically, physically, and optically. Synthetic gems can be distinguished under a microscope because they are more perfect than natural gemstones and contain no irregularities.
Synthetic diamonds were first made by the General Electric Company in the U.S. in 1955. In their process, carbonaceous compounds are subjected to pressures of 56 metric tons per sq cm (360 metric tons per sq in) at temperatures of 2760° C (5000° F). The diamonds thus produced are suitable only for industrial use.
In the late 1960s a method was developed for “growing” diamonds by heating a diamond particle to a high temperature and subjecting it to methane gas. The gas decomposes into carbon atoms, which adhere to the diamond crystal. The crystal structure of the enlarged diamond is identical to that of a natural diamond. Diamonds of about 1 carat (200 mg or 0.007 oz) have been produced by this method, but their cost is still considerably higher than that of naturally occurring diamonds.
Sapphires are made in an apparatus resembling an oxyhydrogen torch. The flame is directed into a fireclay support inside an insulated chamber. The oxygen gas carries finely powdered pure aluminum oxide into the flame, and the powder fuses into droplets, forming a cylindrical boule, or matrix, on the support. The size of the resulting sapphire is controlled by varying the gas flow, temperature, and amount of powder. Boules weighing up to 200 carats (40 g or 1.41 oz) can be produced by this technique. Perfect rubies and sapphires up to 50 carats (10 g or 0.353 oz) have been cut from such a boule.
Rubies are made by the same process by adding 5 to 6 percent chromium oxide to the aluminum oxide. Colors other than red are produced by adding different metallic oxides. Stars can be added to synthetic rubies or sapphires by adding an excess of titanium oxide to the aluminum oxide powder and heating to temperatures greater than 1000° C (greater than 1832° F). In gems made with this technique, synthetic stars appear sharper than naturally occurring stars.Emeralds, some of which are of gem quality, are synthesized by still-secret methods. They can be distinguished from natural emeralds by their red glow under ultraviolet light.
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Samantha Rose: Exclusive Jewelry Designs is a trusted American company that brings together fresh, inspired jewelry products and designs from around the world. Samantha Rose is dedicated to provide the high quality fine exclusive pearl jewelry for everyone.
Samantha Rose features the best selling exclusively designed and celebrity inspired pearl jewelries. Sell pearl jewelry like necklace, earrings, bracelets, wedding accessories, and custom-made pearl jewelry pieces.
Materials
Turquoise 5mm rondelle, 7 x 3 saucer, and 6mm round Japanese miracle beads
4mm rosaline Swarovski pearls
Turquoise On the Surface metallic thread
Copper heishi
Clear plastic ring from a beading wire spool
Terrifically Tacky Tape
White glue
Notions
Scissors
Step 1: Apply the Tacky Tape so it covers the inside of the spool ring. Remove the protective film.
Step 2: Cut a yard's length of metallic thread and apply a small amount of glue to one end. Allow to dry.
Step 3: Stick the unglued end of the thread to the edge of the Tacky Tape. Wrap the thread around the spool ring from back to front for at least 1/4" across the front. Keep the strands right next to each other so the thread begins to cover the ring.
Step 4: Add beads to the outside of the ring. String a combination of beads or several beads of the same type. Wrap the thread around several times between the beaded sections so that you always cover blank space with the thread.
Finish a thread by sticking it to the inside of the spool. Begin a new one just as you did in Step 3.
Step 5: Finish the bracelet by wrapping thread only for at least 1/4" before the end of the spool ring.
A gem cannot always be identified by sight alone. It is therefore necessary to rely on measurement of the optical properties that can be determined without harming the stone in any way.
The gemologist uses an instrument called a refractometer to measure the characteristic property of the stone, known as refractive index, which is its relative ability to refract light. In addition, an instrument called the polariscope is employed to determine whether a gem is doubly or singly refracting. Emeralds, rubies, sapphires, amethysts, and synthetic rubies and sapphires are all doubly refracting, whereas diamonds, spinels, synthetic spinels, garnets, and glass are singly refracting. A special dark-field illuminator with a binocular microscope is employed for examining the interior of a gemstone to determine whether it is of natural or artificial origin, and to search for inclusions characteristic of a given gemstone.
These tests usually are sufficient to identify the rather limited number of materials used as gemstones; occasionally, however, other instruments are required, including a dichroscope, which measures the property called dichroism, or a spectroscope to determine the characteristic absorption spectra. Hardness, the test ordinarily associated with gem testing, is never used on cut stones by the gemologist.
Another physical test that can be given to an unknown stone is the determination of its specific gravity. For exact determinations various weighing devices are used, but rough approximations of the specific gravity of lighter stones can be made by means of a series of liquids of known specific gravity. If the stone will float in a liquid having a specific gravity of 4 and sink in a liquid with a specific gravity of 3, the specific gravity of the stone must lie between these limits and be approximately 3.5.
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