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Gemstones are minerals, rocks, or organic matters that have been chosen for their beauty, durability, and rarity and then cut or faceted and polished to make jewelry or other human adornments. Even though most gemstones are hard, some are too soft or fragile to be used in jewelry, so they are often exhibited in museums and sought by collectors. Gemstones Color Gemstones are diverse in their beauty, and many are available in a stunning variety of shades and colors. Most gemstones have little beauty in the rough state, they may look like ordinary rocks or pebbles, but after a skilled cutting and polishing the full color and luster can be seen. Generally, gemstones with clear, medium-tone, intense, and saturated primary colors are most preferred. Gemstones Clarity Gemstones are formed below the Earth's surface and can sometimes show traces of other minerals, called inclusions. Inclusions can look like small spots or imperfections within the stone. When viewed through a microscope or a 10x loupe, they can give information about the geological environment in which the mineral was formed and its origin. Inclusions can sometimes identify gemstones and even prove whether the stone is natural or synthetic. Some gemstones, such as emeralds, are more likely to have inclusions. Others, such as aquamarine and topaz, generally have very few inclusions or even none at all. Gemstones Cut The natural beauty of a gem can be enhanced by the way it is cut. There are two basic kinds of gem cuts: cabochon and faceted. The cabochon cut has a smooth rounded top, usually with a flat base, and it is mainly used for opaque or translucent softer gemstones. Cabochons were the only way in which stones were cut until about the 14th century when faceting was developed. Faceting is the process of cutting a gemstone to improve its beauty by making it reflect more light. The faceted cut has many flat cut surfaces (facets) with an overall shape that might be round, oval, square, and more. Only the harder gemstones can be successfully faceted. A gemstone that has been cut and polished is called a gem, or jewel. Gemstones Carat The weight of the gemstone is measured in carats (5 carats = 1 gram). It's important to recognize that some gems are denser than others. For example, a one-carat ruby (very dense) is going to be smaller than a one-carat emerald (less dense). Also, different types of gems that are similar in size may still differ significantly in value. Gemstones Hardness The hardness of a stone is the only factor in determining gem durability. It indicates the stone’s resistance to scratching and abrasions, or how the surface of the gem will respond to contact with a sharp point. The Mohs Scale rates the hardness of gems and minerals on a relative scale of 1 (softest – Talc) to 10 (hardest – Diamond). Introduced in 1822, the scale originated when Friedrich Mohs chose ten minerals and assigned numbers to them based on the relative ease or difficulty with which one can be scratched by another. Gemstones Formation Our planet, which was created about 4.5 billion years ago, is comprised of several layers: the Earth's crust, ranging from 3 to 25 miles deep, the mantle and the inner part of Earth known as the core. Most of the gemstones form as minerals under various conditions in the rocks of the Earth’s crust, while just a few of them form in the mantle. The crust is made up of three kinds of rock, known in geology as igneous, metamorphic and sedimentary rock. All gemstones are mined in the crust. After they are mined, they usually go to a lapidary, which does the final cleaning. This may involve grinding off the matrix or rock, in which the gemstone was buried, and then cutting or faceting and polishing the gemstones. A gemstone that has been cut and polished is called a gem, or jewel. Gemstones Species and Varieties Many types of gemstones belong to groups or species which share a common crystal structure and chemical composition. Some of the most important gemstone species include beryl, corundum, garnet, quartz, and tourmaline. Further, each species may have one or more varieties, which have special coloring or features. For instance, the species corundum includes the varieties ruby and sapphire. However, not every gemstone variety belongs to a group, many are unique varieties that don't share properties with any other kind of gem. For instance, peridot, zircon, topaz, and spinel. Minerals vs. Non-Mineral Gemstones Although most gemstones are considered minerals, some are also non-mineral. Minerals occur naturally in the Earth’s crust and are defined as inorganic substances that have a characteristic chemical composition and crystalline structures. Minerals are identified by their distinctive properties, such as color, hardness, crystal form, specific gravity, luster, fracture, and tenacity. When a mineral is regarded as rare and exceptionally beautiful, we refer to it as a gemstone (for instance diamond, emerald, ruby, and sapphire). All minerals can be gemstones, but not all gemstones can be minerals. Also, rocks are comprised of minerals, but minerals are not comprised of rocks. A rock is an inorganic, solid, and natural substance without any specific atomic structure or chemical composition. Its an aggregate composed of two or more minerals which are all firmly locked together to form a hard solid. Non-mineral or organic gemstones are derived from living organisms like animals and plant life, that have formed into beautiful gemstones due to natural processes — for instance, pearl, coral, amber, ivory, and jet. Precious vs. Semi-Precious Gemstones One of the major properties of gemstones is whether they are classified as precious or semi-precious. This is a marketing term designed to make specific stones seem more rare or important than others. Precious gemstones have beauty, durability, and rarity, whereas semi-precious gemstones have only one or two of these qualities. Diamonds, emeralds, rubies, and sapphires are all considered to be precious, and thereby, the most valuable and most desirable. All other gemstones are considered semi-precious. Natural vs. Synthetic Gemstones Natural gemstones are found in nature, created deep in the Earth and mined out of it. They are sometimes enhanced, which means they were treated in some way to improve their color or clarity. This often involves heat or delicate chemical processes. Depending on the type and extent of treatment, they can affect the value of the stone. Synthetic or Lab-created gemstones, on the other hand, are formed in laboratories by human hands and machines. They are chemical, physical, and optically identical to gems found in nature. Of course, lab-created gemstones don't have the rarity of natural gemstones, which is why they are less valuable. Nowadays, synthetic versions of nearly all popular gemstones are available. Some modern synthetic gemstones look more natural and are more difficult to identify, but an experienced jeweler or gemologist can usually detect them. Simulant Gemstones Simulant or imitation gemstones can be anything that resembles the natural gemstones but does not have the same physical characteristics or chemical composition. These items are usually much less expensive than natural forms. Simulant stones are often made of glass or plastic, and most can be detected easily by a jeweler.

gemstone, any of various minerals highly prized for beauty, durability, and rarity. A few noncrystalline materials of organic origin (e.g., pearl, red coral, and amber) also are classified as gemstones. Gemstones have attracted humankind since ancient times, and have long been used for jewelry. The prime requisite for a gem is that it must be beautiful. The beauty may lie in colour or lack of colour; in the latter case, extreme limpidity and “fire” may provide the attraction. Iridescence, opalescence, asterism (the exhibition of a star-shaped figure in reflected light), chatoyance (the exhibition of a changeable lustre and a narrow, undulating band of white light), pattern, and lustre are other features that may make a gemstone beautiful. A gem must also be durable, if the stone is to retain the polish applied to it and withstand the wear and tear of constant handling. Diamonds may be a girl’s best friend, but what is that mineral’s closest relative? Test your knowledge of rocks, minerals, and all things "yabba dabba doo" in this quiz. In addition to their use as jewelry, gems were regarded by many civilizations as miraculous and endowed with mysterious powers. Different stones were endowed with different and sometimes overlapping attributes; the diamond, for instance, was thought to give its wearer strength in battle and to protect him against ghosts and magic. Vestiges of such beliefs persist in the modern practice of wearing a birthstone. Of the more than 2,000 identified natural minerals, fewer than 100 are used as gemstones and only 16 have achieved importance. These are beryl, chrysoberyl, corundum, diamond, feldspar, garnet, jade, lazurite, olivine, opal, quartz, spinel, topaz, tourmaline, turquoise, and zircon. Some of these minerals provide more than one type of gem; beryl, for example, provides emeralds and aquamarines, while corundum provides rubies and sapphires. In virtually all cases, the minerals have to be cut and polished for use in jewelry. Except for diamond, which presents special problems because of its very great hardness (see diamond cutting), gemstones are cut and polished in any of three ways. Agate, opal, jasper, onyx, chalcedony (all with a Mohs hardness of 7 or less) may be tumbled; that is, they may be placed in a cylinder with abrasive grit and water and the cylinder rotated about its long axis. The stones become polished but are irregular in shape. Second, the same kinds of gemstones may instead be cut en cabochon (i.e., with a rounded upper surface and a flat underside) and polished on water- or motor-driven sandstone wheels. Third, gemstones with Mohs hardness of more than 7 may be cut with a carborundum saw and then mounted in a holder (dop) and pressed against a lathe that can be made to revolve with extreme rapidity. The lathe carries a point or small disk of soft iron, which can vary in diameter from that of a pinhead to a quarter of an inch. The face of the disk is charged with carborundum grit, diamond dust, or other abrasives, along with oil. Another tool used to grind facets is the dental engine, which has greater flexibility and sensitiveness than the lathe. The facets are ground onto the stone using these tools and then are polished as described above. Of decisive significance for the modern treatment of gemstones was the kind of cutting known as faceting, which produces brilliance by the refraction and reflection of light. Until the late Middle Ages, gems of all kinds were simply cut either en cabochon or, especially for purposes of incrustation, into flat platelets. The first attempts at cutting and faceting were aimed at improving the appearance of stones by covering natural flaws. Proper cutting depends on a detailed knowledge of the crystal structure of a stone, however. Moreover, it was only in the 15th century that the abrasive property of diamond was discovered and used (nothing else will cut diamond). After this discovery, the art of cutting and polishing diamonds and other gems was developed, probably in France and the Netherlands first. The rose cut was developed in the 17th century, and the brilliant cut, now the general favourite for diamonds, is said to have been used for the first time about 1700. In modern gem cutting, the cabochon method continues to be used for opaque, translucent, and some transparent stones, such as opal, carbuncle, and so on; but for most transparent gems (especially diamonds, sapphires, rubies, and emeralds), faceted cutting is almost always employed. In this method, numerous facets, geometrically disposed to bring out the beauty of light and colour to the best advantage, are cut. This is done at the sacrifice of material, often to the extent of half the stone or more, but the value of the gem is greatly increased. The four most common faceted forms are the brilliant cut, the step cut, the drop cut, and the rose cut. In addition to unfaceted stones being cabochon cut, some are engraved. High-speed, diamond-tipped cutting tools are used. The stone is hand-held against the tool, with the shape, symmetry, size, and depth of cut being determined by eye. Gemstones can also be made by cementing several smaller stones together to create one large jewel. See assembled gem. In some cases, the colour of gemstones is also enhanced. This is accomplished by any of three methods: heating under controlled conditions, exposure to X rays or radium, or the application of pigment or coloured foil to the pavilion (base) facets. In recent times various kinds of synthetic gems, including rubies, sapphires, and emeralds, have been produced. Two methods of fabrication are currently employed, one involving crystal growth from solution and the other crystal growth from melts.

he booming worldwide trend for healing gemstones has seen crystals of all shapes and sizes move from small boutiques owned by friendly hippies and wiccans to the runways of Paris fashion houses and websites owned by Hollywood superstars. What is the spiritual meaning of a gemstone? A gemstone's spiritual meaning is the emotional and physical benefits that it can bring into your life. Amethyst relieves stress, rose quartz brings love, black tourmaline protects from harmful energies and so on. If you have ever wanted to know what powers your favorite gemstone possesses or which stone can be a positive influence, this is where to start. History and archaeology can tell us that gemstones have been appreciated for their spiritual powers just as much as their beauty since we first plucked them from riverbeds or sandy shores. Ancient Egyptians, Assyrians, Greeks and Romans bedecked themselves in protective amulets, pendants and bracelets made of lapis lazuli, carnelian, amber, agate and quartz not only for daily wear but even for the journey into the afterlife. With the arrival of the industrial age and modern medicine you would think it was game over for healing crystals but they are probably more popular now than at any time in history. Whether it is a distrust of pills, a dislike of indifferent and disbelieving doctors or a desire to avoid invasive treatments many people turn to gemstones for help both physical and emotional. What gemstones are considered lucky? Even the most pragmatic and down-to-earth people cannot help believing in 'Luck' - both good and bad. Our earliest creative art was to carve good luck amulets from gemstones to protect us from misfortune but what gemstones are considered the luckiest of all? Is it Aventurine - the gambler's stone, Citrine - the success stone, Malachite to ward off the evil eye or is there a luckier one out there? I would be the first person to recommend visiting a qualified medical practitioner if you have any ailment - either in body or spirit - but there is no denying the benefit of crystals. It could be all down to a positive placebo effect but so long as it works, who cares? We have several detailed articles on various gemstones that have a history and reputation for the spiritual strengths but here we have a mini guide to many of our most popular gemstones as an introduction to their best assets. What gemstone means love? Love has inspired poetry, books, songs, duels, war, devotion and lifetime commitment but can a gemstone bring love, passion and romance to your life? We think so, yet which gemstone is best for love? A deep red ruby is surely the most sensual of gemstones and what about romantic pink tourmalines or the deeply symbolic green emerald?