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The value of colored gemstones, like diamonds, depends on "the 4 C's". Those are Color, Clarity, Cut and Carets. Unlike diamonds, the value of a colored gemstone is effected most by the color. Color is judged by three criteria: Hue, Saturation and Tone. Generally, stones with strong, pure hues are are more valuable. For instance a slightly orangish red Ruby will be much less valuable than a stone that is pure red. Saturation refers to the intensity of the color. Highly saturated colors are very vivid. Less saturated colors tend to be more brownish or grayish. Tone refers to how light or dark a color is. For example, pink would be a light tone of red. Stones with a very dark tone will be almost black. The standards are different for different types of stones, but generally the best stones are ones with pure hues, vivid colors and moderate saturation (not too dark or too light). Clarity takes into account the inclusions in the gemstone. Inclusions are spots, fractures, imperfections, or anything that interferes with the passage of light through the stone. Generally, a stone with fewer inclusions is more valuable. Virtually all stones have some inclusions. Some varieties tend to have more than others and so inclusions are more acceptable in some stones. The best example is Emeralds. They almost always have visible inclusions and so their value won't be effected as much by inclusions as would an Amethyst, for instance, because there is a lot of very "clean" Amethyst available. The Gemological Institute of America has classified all common gemstones into 3 types, based on how included they tend to be, and defined standard clarity grades for each type. You can see their Clarity Grade Chart here. Cut refers to how well faceted the stone is. The stone should be well proportioned, and symmetrical. The facet junctions (where the facets meet) should be crisp and come together in a single point. The surface should be smooth and well polished. The quality and the craftsmanship of the cut has a profound effect on the overall beauty of a gem and so has a significant impact on its value. "Caret" refers to the weight of the stone. Obviously a bigger stone is worth more than a smaller stone of the same quality. With some varieties of gems, a larger stone will be more valuable "per caret" than a smaller one, because larger sizes are much more rare. This is the case with sapphires. A 3 caret sapphire will be worth much more than Twelve 1/4 ct. sapphires. In other cases, like Citrine, where large sizes are readily available, the price per caret will be about the same, or may even be less for the larger stone. Obviously, this is a complex subject. In future articles we will look at some of the topics I've mentioned here in more detail. But, hopefully this has given you an overview of the factors involved in evaluating a gemstone and some basis for comparisons when you are making your next buying decision. If you have any further questions you can email me at brett@palmbeachgems.com . If I don't know the answer, I can probably find it.
Lapis Lazuli is one of the most popular gemstones in the history of mankind and probably one of the first. Throughout recorded history reference is made to this treasured, blue gem. Lapis is the Latin word for “stone” and lazuli comes from the Arabian word “azul”, meaning “blue” In some ancient civilizations it was called sapphire and many references to sapphire in ancient texts, like the Bible, probably refer to lapis rather than the blue corundum that we call sapphire today. It was a popular stone for “scarabs” in ancient Egypt, as well as ornaments and seals in Babylon and Assyria. For centuries, besides its use as a gemstone, lapis was used as a colorant. Pulverized lapis was used as eye make-up in ancient Egypt and to make the ultramarine blue paint that was used by the Grand Masters of the Renaissance. Discovery of Lapis dates back to at least the 7th Century B.C. in Afghanistan. From there it was transported by caravans and traded throughout the known world. Marco Polo once visited the lapis mines of Afghanistan. Today, the finest lapis still comes from Afghanistan. The oldest continually working mines in the world are the lapis mines in the Badakshan region of that country. Lapis also comes from Chile, Pakistan, Russia, the United States and Canada. Lapis Lazuli is popular for beads, carvings and gemstones. The gemstones, as is the case with most opaque gems, are generally cabochon cut. Lapis Lazuli is made up mostly of the mineral Lazurite. Its blue color comes from its Sulpher content. Lapis also commonly contains inclusions of white or grey calcite and golden flecks of pyrite. The finest, most valuable Lapis Lazuli is usually deep, intense blue, with little or no visible calcite and a light dusting of small, evenly distributed pyrite specks. Lower grade, less valuable Lapis will have more white or grey areas. The color can vary from a very dark, midnight blue to a bright royal blue to a soft, mottled blue that is often referred to as Denim Lapis because it resembles faded denim. Prices vary depending on the quality. Retail prices are generally in the range of $1 to $13 per caret. Lapis Lazuli is often dyed to make the color better. It is also often impregnated with resin or wax to improve the color or finish. When purchasing lapis lazuli, always ask if it has been dyed or treated. Often dying can be detected by looking at the stone with a hand lens. You can also try rubbing a suspected stone with a swab soaked in a solvent like fingernail polish remover. If the stone has been dyed, some of the blue color will come off on the swab. However, a salesperson in your local jewelry store might not appreciate you rubbing his jewelry with solvents. So, your best bet, as always, is to deal with a reputable dealer who you trust and who has a reasonable return policy. Don’t buy through the mail or on the internet unless you have the right to return the stone after inspecting it. There is also a lot of imitation lapis on the market. Pyrite inclusions have long been taken as an indication that a stone was genuine, but there are some very good imitations that are complete with pyrite inclusions! Most simulants though, are recognizable with a hand lens. Simulants will usually be “single phase” material, whereas, it can be seen with the lens that Lapis is made up of more than one mineral. Lapis Lazuli is a timeless gemstone, with a rich history dating back to the dawn of recorded time. It has always been in sought after for its rich blue color, its durability and luster and it will always be in fashion. Jewellery: Popular Gemstones - Garnet to Turquoise GARNET - Garnets are found in various shades and colours from brown to purple shades. But its dark red variety is valued as a precious stone although the mineral is quite common. Garnet crystals are 12 faced. The stones have been prized in jewellery for over 5000 years. When many garnet crystals are gathered in a rock cavity they are likened to a ripe pomegranate. Cut as brilliants, garnets are used as ring stones with large ones as pendants, often with cabochon cut and carved. Garnets and star garnets from are found in Australia. JADE - This is the name given to both nephrite and jadeite which are tougher than steel although not particularly hard. China, New Zealand and Alaska supply good Jade. Burma also. Brazil it occurs naturally Used since Neolithic times for weapons and tools and later for delicate carvings. Aztecs used jade. In ancient Egypt the stone was called Nemehen. Pure Jade is white with impurities causing different colours and most pieces are mottled. It is generally translucent or opaque green in colour and is lustrous rather than brilliant. The most prised of all jades is "imperial jade" the transparent emerald green coloured by chromium. It has been always revered in China as a sacred stone. Its quality as a gemstone is judged by the intensity of the green colour and its coolness to the touch. Jadeite is the rarer of the jades and Myanmar remains the only commercial source. Much of the Central American jadeite originates in Guatemala. Soapy jade is the term for the inferior grades used commonly for carving decorations, lamp stands etc. LAPIS LAZULI - This stone consists of blue silicate lazurite with variable amounts of calcite and the brassy gold flecks of pyrite which is more abundant in the poorer quality material. Afghanistan has the best quality that consists mostly of lazurite and is deep blue. In ancient times it was also known as "sapphirus". The Egyptians used to ground it into pigment to use in paintings and murals and in eye shadow and used in manufacture of amulets and symbols, particularly in the representations of the goddess Isis and in the Sacred Eye of Horus. Later it was ground for use as pigment in religious paintings for the glorious blue of the Madonna's robes. In China, royal seals and carvings were made of it. It is considered as a sacred stone in Buddhism. Lapis lazuli is one of the most ancient in items of jewellery - having been known and used for over 6000 years. It was mined in Afghanistan and Siberia near Lake Baikal, but nowadays produced profusely in Chile. MOONSTONE - Moonstone is a Feldspar, comprised of calcium sodium or potassium aluminium silicates. Sri Lanka is the most important source of Moonstone. India produces strongly coloured stones as beige, pink, green, yellow, grey, white and brown. It is considered to be a sacred stone in India and by tradition, it is always cut en cabochon. It is an important stone in Ayurvedic medicine. Beautiful sheens come as with other stones, with subjected light and its particular sheen is called "adularescence" and most prized when the sheen is bluish in colour. Throughout the world it is associated with the Moon and very popular semi precious stone is used in jewellery everywhere. Their fascination lies in their gentle glowing and elusive sheen and above all the softness of their quality, compared with the strength and brilliance of faceted jewels. OPAL - Opal is one of the few gem minerals which is non crystalline. Opals are referred to in history and in legend. Pliny is said to have liked it and Orpheus is said to have declared that the opal 'fills the heart of the gods with joy". Shakespeare refers to ... "this miracle and Queen of gems". Opal consists of pure silica (silicon combined with oxygen) with traces of numerous compounds which explains the many differing types. Opals were rare in antiquity. It is thought to have become commonly known only after the time of Alexander the Great. The only known mines in the earliest times were the Carpathian Mountains. The stone is extremely porous with the weight varying in proportion to the amount of contained water. The colours are determined by structure and the light which causes ever changing effect. Finest opal and opalized wood and fossils are found also in Australia at Coober Pedy and Andamooka. France also supplies some and also Idaho... Opals are usually cut as en cabochon. Their varieties include - Hungarian opals are very fine and were once popular in Europe. Mexican Opals fine transparent variety of opal - Black opals are extremely vivid flashes of colour including red, with dark background and of highest value Milky opal or white opals are opaque with smaller and less spectacular softer markings and colours. Fire opals or Harlequin Opal is the finest quality and variety of gemstone Water Opal is clear and colourless with internal play of colour. Rose Opal or potch opal has a beautiful pink colour but opaque. Hydrophane Opal is opaque but appears colourless in water. PEARL - Along with Coral, this extremely popular gemstone used in jewellery, is found in the seas not the land and is therefore not of the same composition nor characteristics of the earth born gemstones. Care must be taken to preserve the quality of pearls. Pearls are made of calcium carbonate formed within an oyster. The basic irritant is usually a grain of sand which stimulates the oyster to cover it with its own body secretion - eventually forming the well known round and perfect pearl. The lustre of the pearl comes from minute crackles on its surface - finer than those on opals. Their lustre increases in the body warmth of human beings and therefore the practice of allowing the shop attendants to wear the strings of pearl has a practical basis. Different pearl qualities depend upon colour and size and range from the tiniest "seed pearls" to the rare gems of considerable size Harvesting pearls from the wild is singularly unrewarding and cultured pearls have been able to meet the demand for these beautiful natural ornaments. Cultured pearls have been produced in China for several centuries as now in Japan, Australia and the Pacific. RUBY - Next to diamond, rubies (and sapphires) are the most valued of the gems. Ruby is a variety of corundum, When the corundum includes chromium, it becomes ruby, when it contains titanium and iron instead and therefore is blue - the sapphire. The world's finest come from Myanmar, Pakistan and Afghanistan, also Burma, Thailand, India and Ceylon .Burmese ones are exceptionally beautiful - found near Mogo N.E. of Mandalay. "Pigeon Blood" rubies are the highest in the scale of value. Thai Rubies are often found with spinel and are darker red than the Burmese Rubies. A fine ruby is a magnificent gemstone. Ruby has been synthetically produced successfully since 1904. But the genuine rubies are valued because of their rarity and therefore have not dropped in commercial value, in fact have risen. Rubies are also used in Space research in connection with communication systems to cut out surface sounds of the earth and pick up beams from space. SAPPHIRE - Pink Sapphires, Blue sapphires and Yellow Sapphires are found in Thailand and East Africa. They are next to diamond in hardness and therefore resistant to wear. Australia is the largest producer of blue and golden sapphires. Non-blue sapphires are White Sapphires or Golden Sapphires. The largest sapphire known was 950 carats from Burma. The largest in Australia was 886 carats from Queensland in 1934. There are star sapphires and star rubies found which contain fine fibre crystals giving star effect when cut in en cabochon. TOPAZ - Topaz is an aluminium silicate containing about 20% water and fluorine and comes in several colours. Yellow quartz is sold today under the name of topaz and it is one of the most popular colours, although there are others which are greenish and of reddish tint.. Golden Topaz from Brazil is a golden brown to pink colour. The main suppliers are Brazil, Germany and Russia. Japan also produces topaz. Topaz is harder than Rock crystal and is known for its huge crystals - a colourless one from Brazil was found weighing as much as 600 pounds, well formed and clear throughout. The largest known topaz was cut in 1977 and weighed 21,327 carats. Another is known at 36,853 carats. Found in Australia topaz is usually light yellow, green and blue also. Hardness 8 and Orthorhombic crystals brilliant and beautiful stone found in quartz rose rocks. Associated with tin ores . Tinted by heating. Sky blue topaz found in the Scottish Highlands, Brazil and Siberia. TURQUOISE - This stone is composed of aluminium copper sulphate hydrated phosphate of aluminium and copper) and is only medium hard. Egyptians are the first people known to mine it in Sinai over 6000 years ago. The finest is said to be found in Naishapur, Iran, where it has been mined for about 3000 years. It is found also in Sinar, Turkestan and Tibet. The colours range from pale blue to deep green/blue. Water content affects the colour of the stone. It responds to human touch and warmth and in the Middle East is used as a reflector of babies' health in the crib etc. It is relatively soft and has a waxy lustre. It is porous and its colour may deteriorate if skin oils and cosmetics are absorbed during wear. It's famous for its change of colour when difficult influences are near and for this reason was attached to cradle of babies to reflect the child's vitality and to alert them to any change in tone and colour. Some believe it becomes moist and changes colour when warning against Poison. The gem is regarded as a pledge of true affection and drawing evil influences. The green variety is found in New Mexico and in Australia. Michael Russell Your Independent guide to Jewellery Article Source: http://EzineArticles.com/?expert=Michael_Russell Brilliance and scintillation are terms that are commonly used to describe a gemstone. Although they are related, they are not the same thing and there is often confusion over exactly what they mean. I hope here, to shed a little light on the issue (pun intended). They both describe how light interacts with a faceted gemstone. Brilliance is sometimes referred to as “internal luster” or “liveliness”. It is the amount of light entering a stone that is returned to the eye of the viewer. It is in that brilliance that you see the color of the gem. The amount of brilliance is dependant on the type of stone, its clarity, and how it is cut. A stone that is not well cut and proportioned will “leak” light from the back of the stone. The result is dull or dark looking areas, called “areas of extinction”, when viewing the stone face up. With many commercially faceted gemstones, if you look down through the top of the stone, you can see through the bottom. This is called a window and is not ideal. In a well cut gemstone, the light passing through the top of the stone will not pass straight through but will be reflected back and the stone will be said to have more “brilliance”. If a stone is heavily included, the inclusions can diffuse or absorb some of the light entering the stone and reduce the brilliancy, making the stone appear fuzzy. Brilliance is sometimes described as a percentage, indicating the percentage of light entering the stone that is being reflected back. Scintillation is sparkle. It’s the flashes you see as you move a stone in the light. It is determined by the optical properties of the particular gemstone and how it is faceted. The number of facets affects the amount of scintillation a stone shows. A gem cut with a smooth cone-shaped pavilion (the bottom part of the stone), could have high brilliance, but very little scintillation. Another related term is “dispersion” or “fire”. It refers to the light being split into the spectral colors before it is reflected back to the eye. That’s the multi-colored flickering effect that diamonds are famous for. You also see it of course, in cubic zirconia and in a few colored gems. You will see these terms used often in describing gemstones. Sometimes they are used correctly and sometimes not. As with most things there are disagreements over the exact definitions of the words. Hopefully, the next time you encounter one of these terms, you will have a little better grasp of exactly what the speaker or writer was trying to convey.
Tips for Buying Jewelry Online Over the last few years, the Internet has quickly become one of the most important venues for purchasing all types of jewelry in all price ranges. There are great opportunities for a smart buyer to find some fabulous deals, but also the possibility of being overcharged or outright defrauded if you aren’t careful. Dealers selling jewelry online have much less overhead than traditional jewelry stores and they often have more direct sources for their products. This means that they really can sell for less. But buying something that you can’t see in person and touch from somebody that you don’t know is obviously fraught with danger. This article will provide you with some of the basic things you need to consider before you go shopping on-line for the ultimate jewelry bargain. First of all, just as if you were buying in a brick and mortar store, you need to inform yourself ahead of time about the product that you are buying. If you are interested in buying gemstone jewelry, do some research on the internet regarding what makes one gemstone better than another. Learn a little about what the 4 C’s mean. Briefly, they stand for color, clarity, cut and carets. Those are the 4 attributes of a gemstone that determine its quality. Its quality combined with supply and demand, determine its value. Armed with a little knowledge, you’ll know what attributes to look for in the ads and listings you come across and you’ll know what questions to ask. The ruby in a particular ring may be large and a nice shade of red, but if it has serious inclusions (flaws) or it is not well faceted to achieve maximum brilliance, it may not be worth much. Also do some research on gemstone “treatments”. Many if not most gemstones on the market today have been treated in some way to enhance their color or clarity. Some enhancements are considered acceptable. Some are not! Some may not even be permanent. Dealers must disclose any treatments done to the gemstones they are selling. Be sure and ask. Also familiarize yourself with common jewelry related terminology. For example make sure you understand the differences between 10 Karat gold and 14 Karat gold, Gold filled and gold plated, etc. The differences in value and quality are considerable! Make sure you understand the meanings of terms like genuine, natural, simulated, created and imitation. The differences are often subtle, but important. Read all the sales copy carefully. As much as possible, know who you are dealing with. If you are shopping on eBay or some similar site, check the seller’s feedback carefully. If it is an independent website, look to see if they have any professional affiliations. Find out how long they have been in business. Do they list a phone number on their site so you can call them directly if there is a problem or question. Also note where they are located. If they are doing business in another country, they may be trustworthy, honest people, but if they aren’t you may not have any recourse once they have you’re money. You can often get a much lower price buying from some less developed country, but in my opinion, the risks are much greater. Third, make sure the seller has a reasonable return policy. You are buying something that you can’t see or hold in your hand. Even the most honest seller is trying to present his merchandise in the best light. Even the best photographs don’t tell the whole story. Colors can vary from one computer monitor to another. It is fair and reasonable that you should have the opportunity to return your purchase if it doesn’t live up to your expectations. You will probably be responsible for paying the shipping for returned merchandise and some dealers charge a “restocking fee”. Just make sure you know before you send your money, what the seller’s return policy is. That’s about it! Due some research, ask questions and use common sense and you’ll be able to pick up some terrific bargains when buying jewelry on the Internet. Bali beads are a style of
hand-crafted silver beads made in Bali, Indonesia. They come in a wide variety
of patterns. But the variations are endless. Bali spacer beads are often in the shape of daisies or stars. Bali Beads usually are made with an antiqued finish, where the low spots in the patterns are oxidized and the high spots are polished. Since Bali Beads have become so popular, they have been imitated by manufacturers in a number of other countries. "Bali-style" beads often are made in Turkey, India, Israel and China as well as in Indonesia. In some cases the quality is not as good, but sometimes the beads from places other than Bali are just as good or better. The beads are unmarked so it is not possible to know for sure where they were produced. A more important consideration is the silver content of the beads. Bali beads are approximately .925 pure silver, but some manufactures use less pure silver, silver plating or pewter. Sometimes that is done to offer a less expensive option but sometimes it is a deliberate attempt to deceive. Before you buy Bali beads, take note of the silver content and buy from a trusted source and one that guarantees their products. Since Bali beads are individually hand-made there will be slight imperfections and variations from one bead to the next. That is part of the character of the beads and should not be considered a flaw unless there are very great differences. Bali beads offer a wide array of design possibilities. Sometimes bracelets or other pieces are made entirely of silver Bali beads strung together in various arrangements. More often they are combined with beads of other materials like gemstones, Swarovski crystals or pearls to make necklaces, bracelets and earrings. Whatever style or materials you like to use, you will probably find applications for Bali beads that will add character and originality to your designs. ZIRCON
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