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84-564: Emerald is a gemstone and a variety of the mineral beryl (Be 3 Al 2 (SiO 3 ) 6 ) colored green by trace amounts of chromium or sometimes vanadium . Beryl has a hardness of 7.5–8 on the Mohs scale . Most emeralds have many inclusions , so their toughness (resistance to breakage) is classified as generally poor. Emerald is a cyclosilicate . The word "emerald" is derived (via Old French : esmeraude and Middle English : emeraude ), from Vulgar Latin : esmaralda/esmaraldus ,

168-492: A "synthetic" stone. The FTC says: "§ 23.23(c) It is unfair or deceptive to use the word "laboratory-grown", "laboratory-created", "[manufacturer name]-created", or "synthetic" with the name of any natural stone to describe any industry product unless such industry product has essentially the same optical, physical, and chemical properties as the stone named." The virtue of the Emerald is to counteract poison. They say that if

252-463: A certificate from a licensed, independent gemology laboratory. Other treatments, for example the use of green-tinted oil, are not acceptable in the trade. Gems are graded on a four-step scale; none , minor , moderate and highly enhanced. These categories reflect levels of enhancement, not clarity . A gem graded none on the enhancement scale may still exhibit visible inclusions. Laboratories apply these criteria differently. Some gemologists consider

336-553: A clearing oil. Today, cedarwood oil is often used for its aromatic properties, especially in aromatherapy ; it can also be used to renew the smell of natural cedar furniture. Cedarwood oil is used as an insect repellent , both directly applied to the skin and as an additive to sprays, candles and other products. In India, oil from the deodar cedar ( Cedrus deodara , a true cedar) has been shown to possess insecticidal and antifungal properties and to have some potential for control of fungal deterioration of spices during storage. It

420-442: A cubic crystal system, are often found as octahedrons . 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 sapphire. Other examples are the emerald (green), aquamarine (blue), red beryl (red), goshenite (colorless), heliodor (yellow), and morganite (pink), which are all varieties of

504-504: A diamond. With modification, these categories can be useful in understanding the grading of all gemstones. The four criteria carry different weights depending upon whether they are applied to colored gemstones or to colorless diamonds. In diamonds, the cut is the primary determinant of value, followed by clarity and color. An ideally cut diamond will sparkle, to break down light into its constituent rainbow colors (dispersion), chop it up into bright little pieces (scintillation), and deliver it to

588-447: A gemstone is a natural stone or synthetic, the chemical, physical, and optical characteristics are the same: They are composed of the same mineral and are colored by the same trace materials, have the same hardness and density and strength , and show the same color spectrum , refractive index , and birefringence (if any). Lab-created stones tend to have a more vivid color since impurities common in natural stones are not present in

672-433: A more desirable blue / purple color. A considerable portion of all sapphire and ruby is treated with a variety of heat treatments to improve both color and clarity. When jewelry containing diamonds is heated for repairs, the diamond should be protected with boric acid ; otherwise, the diamond, which is pure carbon, could be burned on the surface or even burned completely up. When jewelry containing sapphires or rubies

756-487: A number of inclusions), cut, unusual optical phenomena within the stone such as color zoning (the uneven distribution of coloring within a gem) and asteria (star effects). Apart from the more generic and commonly used gemstones such as from diamonds , rubies , sapphires , and emeralds , pearls and opal have also been defined as precious in the jewellery trade. Up to the discoveries of bulk amethyst in Brazil in

840-414: A particular stone. Eye-clean stones of a vivid primary green hue (as described above), with no more than 15% of any secondary hue or combination (either blue or yellow) of a medium-dark tone, command the highest prices. The relative non-uniformity motivates the cutting of emeralds in cabochon form, rather than faceted shapes. Faceted emeralds are most commonly given an oval cut, or the signature emerald cut,

924-607: A rectangular cut with facets around the top edge. Most emeralds are oiled as part of the post- lapidary process, in order to fill in surface-reaching cracks so that clarity and stability are improved. Cedar oil , having a similar refractive index , is often used in this widely adopted practice. Other liquids, including synthetic oils and polymers with refractive indexes close to that of emeralds, such as Opticon , are also used. The least expensive emeralds are often treated with epoxy resins, which are effective for filling stones with many fractures. These treatments are typically applied in

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1008-626: A result of this is the exploitation of natural resources and labor within gemstone mining operations. Many mines, particularly in developing countries, face challenges such as inadequate safety measures, low wages, and poor working conditions. Miners , often from disadvantaged backgrounds, endure hazardous working conditions and receive meager wages, contributing to cycles of poverty and exploitation. Gemstone mining operations are frequently conducted in remote or underdeveloped areas, lacking proper infrastructure and access to essential services such as healthcare and education. This further contributes to

1092-400: A scale where 0% tone is colorless and 100% is opaque black. In addition, a fine emerald will be saturated and have a hue that is bright (vivid). Gray is the normal saturation modifier or mask found in emeralds; a grayish-green hue is a dull-green hue. Emeralds tend to have numerous inclusions and surface-breaking fissures . Unlike diamonds, where the loupe standard (i.e., 10× magnification)

1176-626: A stone is untreated, while another lab might conclude that it is heat-treated. To minimize such differences, seven of the most respected labs, AGTA-GTL (New York), CISGEM (Milano), GAAJ-ZENHOKYO (Tokyo), GIA (Carlsbad), GIT (Bangkok), Gübelin (Lucerne) and SSEF (Basel), have established the Laboratory Manual Harmonisation Committee (LMHC), for the standardization of wording reports, promotion of certain analytical methods and interpretation of results. Country of origin has sometimes been difficult to determine, due to

1260-508: A thin layer of emerald on top of natural colorless beryl stones. Later, from 1965 to 1970, the Linde Division of Union Carbide produced completely synthetic emeralds by hydrothermal synthesis. According to their patents (attributable to E.M. Flanigen ), acidic conditions are essential to prevent the chromium (which is used as the colorant) from precipitating. Also, it is important that the silicon-containing nutrient be kept away from

1344-459: A vacuum chamber under mild heat, to open the pores of the stone and allow the fracture-filling agent to be absorbed more effectively. The U.S. Federal Trade Commission requires the disclosure of this treatment when an oil-treated emerald is sold. The use of oil is traditional and largely accepted by the gem trade, although oil-treated emeralds are worth much less than untreated emeralds of similar quality. Untreated emeralds must also be accompanied by

1428-456: A variant of Latin smaragdus , which was via Ancient Greek : σμάραγδος (smáragdos; "green gem"). The Greek word may have a Semitic, Sanskrit or Persian origin. According to Webster's Dictionary the term emerald was first used in the 14th century. Emeralds, like all colored gemstones , are graded using four basic parameters known as "the four C s": color , clarity, cut and carat weight . Normally, in grading colored gemstones, color

1512-438: A venomous animal should look at it, it will become blinded. The gem also acts as a preservative against epilepsy; it cures leprosy, strengthens sight and memory, checks copulation, during which act it will break, if worn at the time on the finger. Gemstone A gemstone (also called a fine gem , jewel , precious stone , semiprecious stone , or simply gem ) is a piece of mineral crystal which, when cut or polished,

1596-448: Is hardstone . Use of the terms 'precious' and 'semi-precious' in a commercial context is, arguably, misleading in that it suggests certain stones are more valuable than others when this is not reflected in the actual market value, although it would generally be correct if referring to desirability. In modern times gemstones are identified by gemologists , who describe gems and their characteristics using technical terminology specific to

1680-434: Is a common practice. Most citrine is made by heating amethyst , and partial heating with a strong gradient results in " ametrine " – a stone partly amethyst and partly citrine. Aquamarine is often heated to remove yellow tones, or to change green colors into the more desirable blue, or enhance its existing blue color to a deeper blue. Nearly all tanzanite is heated at low temperatures to remove brown undertones and give

1764-509: Is a recognized grading of the gem's luster, transparency, or "brilliance". Very transparent gems are considered " first water ", while "second" or "third water" gems are those of a lesser transparency. Additionally, material or flaws within a stone may be present as inclusions . Gemstones have no universally accepted grading system. Diamonds are graded using a system developed by the Gemological Institute of America (GIA) in

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1848-522: Is also colored to make the emerald appear of better color as well as clarity. Turquoise is also commonly treated in a similar manner. Fracture filling has been in use with different gemstones such as diamonds, emeralds, and sapphires. In 2006 "glass-filled rubies" received publicity. Rubies over 10 carats (2 g) with large fractures were filled with lead glass, thus dramatically improving the appearance (of larger rubies in particular). Such treatments are fairly easy to detect. Another treatment method that

1932-404: Is based on this species. Cedarwood oil was used as the base for paints by the ancient Sumerians. They would grind cobalt compounds in a mortar to produce a blue pigment . They could obtain green from copper , yellow from lead antimonate , black from charcoal , and white from gypsum . One of three methods of ancient Egyptian embalming practices employs the use of cedarwood oil. This

2016-404: Is by far the most important criterion. However, in the grading of emeralds, clarity is considered a close second. A fine emerald must possess not only a pure verdant green hue as described below, but also a high degree of transparency to be considered a top gemstone. This member of the beryl family ranks among the traditional "big four" gems along with diamonds , rubies and sapphires . In

2100-440: Is commonly used to treat gemstones is bleaching. This method uses a chemical in order to reduce the colour of the gem. After bleaching, a combination treatment can be done by dying the gemstone once the unwanted colours are removed. Hydrogen peroxide is the most commonly used product used to alter gemstones and have notably been used to treat jade and pearls. The treatment of bleaching can also be followed by impregnation, which allows

2184-451: Is considered a supplementary test when making a natural versus synthetic determination, as many, but not all, natural emeralds are inert to ultraviolet light. Many synthetics are also UV inert. Synthetic emeralds are often referred to as "created", as their chemical and gemological composition is the same as their natural counterparts. The U.S. Federal Trade Commission (FTC) has very strict regulations as to what can and what cannot be called

2268-515: Is considered to be one of the important gemstones after rubies, emeralds, and sapphires according to Gübelin Gemlab. Even though it is a tourmaline, Paraiba Tourmaline is one of the most expensive gemstones. There are a number of laboratories which grade and provide reports on gemstones. Each laboratory has its own methodology to evaluate gemstones. A stone can be called "pink" by one lab while another lab calls it "padparadscha". One lab can conclude

2352-436: Is divided into three components: hue , saturation , and tone . Emeralds occur in hues ranging from yellow-green to blue-green, with the primary hue necessarily being green. Yellow and blue are the normal secondary hues found in emeralds. Only gems that are medium to dark in tone are considered emeralds; light-toned gems are known instead by the species name green beryl . The finest emeralds are approximately 75% tone on

2436-501: Is emerald (green). Yellow, red and blue beryls are possible but much more rare. Synthetic emerald became possible with the development of the flux growth process and is produced in this way and well as hydrothermal growth. Types of synthetic quartz include citrine, rose quartz, and amethyst. Natural occurring quartz is not rare, but is nevertheless synthetically produced as it has practical application outside of aesthetic purposes. Quartz generates an electric current when under pressure and

2520-563: Is essential. Additionally, investing in community development projects, such as education and healthcare initiatives, can help alleviate poverty and empower marginalized communities dependent on the gemstone industry. Collaboration across sectors is crucial for fostering a more equitable and sustainable gemstone trade that benefits both producers and consumers while respecting human rights and environmental integrity. Synthetic gemstones are distinct from imitation or simulated gems. Synthetic gems are physically, optically, and chemically identical to

2604-419: Is heated, those stones should not be coated with boric acid (which can etch the surface) or any other substance. They do not have to be protected from burning, like a diamond (although the stones do need to be protected from heat stress fracture by immersing the part of the jewelry with stones in the water when metal parts are heated). The irradiation process is widely practiced in jewelry industry and enabled

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2688-410: Is perceived by the viewer as sparkle. There are many commonly used shapes for faceted stones . The facets must be cut at the proper angles, which varies depending on the optical properties of the gem. If the angles are too steep or too shallow, the light will pass through and not be reflected back toward the viewer. The faceting machine is used to hold the stone onto a flat lap for cutting and polishing

2772-503: Is produced in Syria, and how it is used. In Europe, tar is extracted from [ Pinus mugo ] by the agency of fire. ... The first steam that exudes flows ... into a reservoir made for its reception: in Syria this substance is known as “cedrium”; and it possesses such remarkable strength, that in Egypt the bodies of the dead, after being steeped in it, are preserved from all corruption . Until

2856-574: Is still sometimes also used to clarify emeralds . The cedarwood oil of the ancients, in particular the Sumerians and Egyptians , was derived from the Cedar of Lebanon ( Cedrus libani ), a true cedar native to the northern and western mountains of the Middle East . The once-mighty Cedar of Lebanon forests of antiquity have been almost entirely eradicated, and today no commercial oil extraction

2940-663: Is the world's second biggest producer, with its Kafubu River area deposits (Kagem Mines) about 45 km (28 mi) southwest of Kitwe responsible for 20% of the world's production of gem-quality stones in 2004. In the first half of 2011, the Kagem Mines produced 3.74 tons of emeralds. Emeralds are found all over the world in countries such as Afghanistan, Australia, Austria, Brazil, Bulgaria, Cambodia, Canada, China, Egypt, Ethiopia, France, Germany, India, Kazakhstan, Madagascar, Mozambique, Namibia, Nigeria, Norway, Pakistan, Russia, Somalia, South Africa, Spain, Switzerland, Tanzania,

3024-462: Is used in watches, clocks, and oscillators. Cedar oil Although termed cedar or cedarwood oils, the most important oils are produced from distilling wood of a number of different junipers ( Juniperus ) and cypresses ( Cupressus ; both of the family Cupressaceae ), rather than true cedars (of the family Pinaceae ). Similar oils are distilled, pressed or chemically extracted in small quantities from wood, roots, and leaves from plants of

3108-543: Is used to grade clarity, emeralds are graded by eye. Thus, if an emerald has no visible inclusions to the eye (assuming normal visual acuity) it is considered flawless. Stones that lack surface breaking fissures are extremely rare and therefore almost all emeralds are treated ("oiled", see below) to enhance the apparent clarity. The inclusions and fissures within an emerald are sometimes described as jardin (French for garden ), because of their mossy appearance. Imperfections are unique for each emerald and can be used to identify

3192-646: Is used to make jewelry or other adornments . Certain rocks (such as lapis lazuli , opal , and obsidian ) and occasionally organic materials that are not minerals (such as amber , jet , and pearl ) may also be used for jewelry and are therefore often considered to be gemstones as well. Most gemstones are hard, but some softer minerals such as brazilianite may be used in jewelry because of their color or luster or other physical properties that have aesthetic value . However, generally speaking, soft minerals are not typically used as gemstones by virtue of their brittleness and lack of durability. Found all over

3276-526: The FDA as a food additive preservative . The United States EPA "does not expect [toxic] effects to occur among users of currently registered cedarwood oil products" because their use and public exposure is at a lower level and more intermittent than in case studies (e.g., U.S. National Toxicology Program ). The EPA believes there is negligible human and environmental risk posed by exposure to registered cedarwood pesticide if used in properly prescribed manner. All

3360-446: The ancient Greeks , begins with a distinction between precious and semi-precious ; similar distinctions are made in other cultures. In modern use, the precious stones are emerald , ruby , sapphire and diamond , with all other gemstones being semi-precious. This distinction reflects the rarity of the respective stones in ancient times, as well as their quality: all are translucent , with fine color in their purest forms (except for

3444-615: The 1960s, the American jewelry industry changed the definition of emerald to include the green vanadium-bearing beryl. As a result, vanadium emeralds purchased as emeralds in the United States are not recognized as such in the United Kingdom and Europe. In America, the distinction between traditional emeralds and the new vanadium kind is often reflected in the use of terms such as "Colombian emerald". In gemology , color

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3528-415: The 19th century, amethyst was considered a "precious stone" as well, going back to ancient Greece. Even in the last century certain stones such as aquamarine , peridot and cat's eye ( cymophane ) have been popular and hence been regarded as precious, thus reinforcing the notion that a mineral's rarity may have been implicated in its classification as a precious stone and thus contribute to its value. Today

3612-712: The United States, Zambia, and Zimbabwe. In the US, emeralds have been found in Connecticut , Montana , Nevada , North Carolina , and South Carolina . In 1998, emeralds were discovered in the Yukon Territory of Canada. Since the onset of concerns regarding diamond origins, research has been conducted to determine if the mining location could be determined for an emerald already in circulation. Traditional research used qualitative guidelines such as an emerald's color, style and quality of cutting, type of fracture filling, and

3696-517: The anthropological origins of the artifacts bearing the mineral to determine the emerald's mine location. More recent studies using energy-dispersive X-ray spectroscopy methods have uncovered trace chemical element differences between emeralds, including ones mined in close proximity to one another. American gemologist David Cronin and his colleagues have extensively examined the chemical signatures of emeralds resulting from fluid dynamics and subtle precipitation mechanisms, and their research demonstrated

3780-529: The basis of their alleged healing powers. A gemstone that has been rising in popularity is Cuprian Elbaite Tourmaline which is also called "Paraiba Tourmaline". It was first discovered in the late 1980s in Paraíba, Brazil and later in Mozambique and Nigeria. It is famous for its glowing neon blue color. Paraiba Tourmaline has become one of the most popular gemstones in recent times thanks to its color and

3864-559: The cedarwood oils of commerce contain a group of chemically related compounds, the relative proportions of which depend upon the species from which the oil is obtained. These compounds include cedrol and cedrene , and while they contribute something to the odor of the whole oil they are also valuable to the chemical industry for conversion to other derivatives with fragrance applications. The oils are therefore used both directly and as sources of chemical isolates. Cedarwood oils each have characteristic woody odours which may change somewhat in

3948-536: The chemical homogeneity of emeralds from the same mining location and the statistical differences that exist between emeralds from different mining locations, including those between the three locations: Muzo, Coscuez, and Chivor, in Colombia, South America. Both hydrothermal and flux-growth synthetics have been produced, and a method has been developed for producing an emerald overgrowth on colorless beryl . The first commercially successful emerald synthesis process

4032-455: The color from white to blue. Most green quartz (Oro Verde) are also irradiated to achieve the yellow-green color. Diamonds are mainly irradiated to become blue-green or green, although other colors are possible. When light-to-medium-yellow diamonds are treated with gamma rays they may become green; with a high-energy electron beam, blue. Emeralds containing natural fissures are sometimes filled with wax or oil to disguise them. This wax or oil

4116-475: The colorless diamond), and very hard with a hardness score of 8 to 10 on the Mohs scale . Other stones are classified by their color, translucency , and hardness. The traditional distinction does not necessarily reflect modern values; for example, while garnets are relatively inexpensive, a green garnet called tsavorite can be far more valuable than a mid-quality emerald. Another traditional term for semi-precious gemstones used in art history and archaeology

4200-673: The constant discovery of new source locations. Determining a "country of origin" is thus much more difficult than determining other aspects of a gem (such as cut, clarity, etc.). Gem dealers are aware of the differences between gem laboratories and will make use of the discrepancies to obtain the best possible certificate. A few gemstones are used as gems in the crystal or other forms in which they are found. Most, however, are cut and polished for usage as jewelry. The two main classifications are as follows: Stones which are opaque or semi-opaque such as opal , turquoise , variscite , etc. are commonly cut as cabochons. These gems are designed to show

4284-449: The course of drying out. The crude oils are often yellowish or even darker in color and some, such as Texas cedarwood oil (derived primarily from Juniperus ashei and J. deppeana ), are quite viscous and deposit crystals on standing. They find use (sometimes after rectification ) in a range of fragrance applications such as soap perfumes, household sprays, floor polishes and insecticides. Small quantities are used in microscope work as

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4368-444: The creation of gemstone colors that do not exist or are extremely rare in nature. However, particularly when done in a nuclear reactor , the processes can make gemstones radioactive. Health risks related to the residual radioactivity of the treated gemstones have led to government regulations in many countries. Virtually all blue topaz , both the lighter and the darker blue shades such as "London" blue, has been irradiated to change

4452-607: The discovery of the Colombian deposits. Today, only ruins remain in Egypt. Colombia is by far the world's largest producer of emeralds, constituting 50–95% of the world production, with the number depending on the year, source and grade. Emerald production in Colombia has increased drastically in the last decade, increasing by 78% from 2000 to 2010. The three main emerald mining areas in Colombia are Muzo , Coscuez, and Chivor . Rare "trapiche" emeralds are found in Colombia, distinguished by ray-like spokes of dark impurities. Zambia

4536-572: The earliest methods of gemstone treatment date back to the Minoan Age, for example foiling, which is where metal foil is used to enhance a gemstone's colour. Other methods recorded 2000 years ago in the book Natural History by Pliny the Elder include oiling and dyeing/staining. Heat can either improve or spoil gemstone color or clarity. The heating process has been well known to gem miners and cutters for centuries, and in many stone types heating

4620-410: The early 1950s. Historically, all gemstones were graded using the naked eye. The GIA system included a major innovation: the introduction of 10x magnification as the standard for grading clarity. Other gemstones are still graded using the naked eye (assuming 20/20 vision). A mnemonic device , the "four Cs" (color, cut, clarity, and carats), has been introduced to help describe the factors used to grade

4704-410: The eye (brilliance). In its rough crystalline form, a diamond will do none of these things; it requires proper fashioning and this is called "cut". In gemstones that have color, including colored diamonds, the purity, and beauty of that color is the primary determinant of quality. Physical characteristics that make a colored stone valuable are color, clarity to a lesser extent (emeralds will always have

4788-445: The eye as the perceived color. A ruby appears red because it absorbs all other colors of white light while reflecting red. A material which is mostly the same can exhibit different colors. For example, ruby and sapphire have the same primary chemical composition (both are corundum ) but exhibit different colors because of impurities which absorb and reflect different wavelengths of light depending on their individual compositions. Even

4872-439: The fact that these impurities can be "manipulated", thus changing the color of the gem. Gemstones are often treated to enhance the color or clarity of the stone. In some cases, the treatment applied to the gemstone can also increase its durability. Even though natural gemstones can be transformed using the traditional method of cutting and polishing, other treatment options allow the stone's appearance to be enhanced. Depending on

4956-451: The field of gemology . The first characteristic a gemologist uses to identify a gemstone is its chemical composition . For example, diamonds are made of carbon ( C ) and rubies of aluminium oxide ( Al 2 O 3 ). Many gems are crystals which are classified by their crystal system such as cubic or trigonal or monoclinic . Another term used is habit , the form the gem is usually found in. For example, diamonds, which have

5040-417: The flat facets. Rarely, some cutters use special curved laps to cut and polish curved facets. The color of any material is due to the nature of light itself. Daylight, often called white light, is all of the colors of the spectrum combined. When light strikes a material, most of the light is absorbed while a smaller amount of a particular frequency or wavelength is reflected. The part that is reflected reaches

5124-668: The gemstone trade no longer makes such a distinction. Many gemstones are used in even the most expensive jewelry, depending on the brand-name of the designer, fashion trends, market supply, treatments, etc. Nevertheless, diamonds, rubies, sapphires, and emeralds still have a reputation that exceeds those of other gemstones. Rare or unusual gemstones, generally understood to include those gemstones which occur so infrequently in gem quality that they are scarcely known except to connoisseurs, include andalusite , axinite , cassiterite , clinohumite , painite and red beryl . Gemstone pricing and value are governed by factors and characteristics in

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5208-425: The gemstone's durability to be increased. The socio-economic dynamics of the gemstone industry are shaped by market forces and consumer preferences and typically go undiscussed. Changes in demand and prices can significantly affect the livelihoods of those involved in gemstone mining and trade, particularly in developing countries where the industry serves as a crucial source of income. A situation that arises as

5292-451: The genera Platycladus , Cupressus , Taiwania , and Calocedrus . One of the elements found in many cedar trees is cedrol . The amount of cedrol in a species of cedar affects its pesticidal effect on insects. As part of ancient Egyptian funerary practices , cedar oil was used in embalming , which in effect helped to keep insects from disturbing the body. Cedarwood oil is a mixture of organic compounds considered generally safe by

5376-419: The look and color of the real stone but possess neither their chemical nor physical characteristics. In general, all are less hard than diamond. Moissanite actually has a higher refractive index than diamond, and when presented beside an equivalently sized and cut diamond will show more "fire". Cultured, synthetic, or "lab-created" gemstones are not imitations: The bulk mineral and trace coloring elements are

5460-597: The mere presence of oil or polymers to constitute enhancement. Others may ignore traces of oil if the presence of the material does not improve the look of the gemstone. Emeralds in antiquity were mined in Ancient Egypt at locations on Mount Smaragdus since 1500 BC, and India and Austria since at least the 14th century AD. The Egyptian mines were exploited on an industrial scale by the Roman and Byzantine Empires, and later by Islamic conquerors. Mining in Egypt ceased with

5544-435: The mineral species beryl . Gems are characterized in terms of their color (hue, tone and saturation), optical phenomena, luster, refractive index , birefringence , dispersion , specific gravity , hardness , cleavage , and fracture . They may exhibit pleochroism or double refraction . They may have luminescence and a distinctive absorption spectrum . Gemstones may also be classified in terms of their "water". This

5628-516: The most common on the market currently. Synthetic corundum includes ruby (red variation) and sapphire (other color variations), both of which are considered highly desired and valued. Ruby was the first gemstone to be synthesized by Auguste Verneuil with his development of the flame-fusion process in 1902. Synthetic corundum continues to be made typically by flame-fusion as it is most cost-effective, but can also be produced through flux growth and hydrothermal growth. The most common synthesized beryl

5712-538: The natural stone, but are created in a laboratory. Imitation or simulated stones are chemically different from the natural stone, but may appear quite similar to it; they can be more easily manufactured synthetic gemstones of a different mineral ( spinel ), glass, plastic, resins, or other compounds. Examples of simulated or imitation stones include cubic zirconia , composed of zirconium oxide, synthetic moissanite , and uncolored, synthetic corundum or spinels ; all of which are diamond simulants . The simulants imitate

5796-474: The other ingredients to prevent nucleation and confine growth to the seed crystals. Growth occurs by a diffusion-reaction process, assisted by convection. The largest producer of hydrothermal emeralds today is Tairus, which has succeeded in synthesizing emeralds with chemical composition similar to emeralds in alkaline deposits in Colombia, and whose products are thus known as “Colombian created emeralds” or “Tairus created emeralds”. Luminescence in ultraviolet light

5880-689: The pre-existing socio-economic disparities and obstructs community development such that the benefits of gemstone extraction may not adequately reach those directly involved in the process. Another such issue revolves around environmental degradation resulting from mining activities. Environmental degradation can pose long-term threats to ecosystems and biodiversity, further worsening the socio-economic state in affected regions. Unregulated mining practices often result in deforestation , soil erosion , and water contamination thus threatening ecosystems and biodiversity . Unregulated mining activity can also cause depletion of natural resources, thus diminishing

5964-804: The prevalence of illicit practices undermine market integrity and trust. The lack of transparency and accountability in the supply chain aggravates pre-existing inequalities, as middlemen and corporations often capture a disproportionate share of the profits. As a result, the unequal distribution of profits along the supply chain does little to improve socio-economic inequalities, particularly in regions where gemstones are mined. Addressing these socio-economic challenges requires intensive effort from various stakeholders, including governments, industry executives, and society, to promote sustainable practices and ensure equitable outcomes for all involved parties. Implementing and enforcing regulations to ensure fair labor practices, environmental sustainability, and ethical sourcing

6048-450: The prospects for sustainable development . The environmental impact of gemstone mining not only poses a threat to ecosystems but also undermines the long-term viability of the industry by diminishing the quality and quantity of available resources. Furthermore, the gemstone industry is also susceptible to issues related to transparency and ethics, which impact both producers and consumers. The lack of standardized certification processes and

6132-507: The quality of the stone. These characteristics include clarity, rarity, freedom from defects, the beauty of the stone, as well as the demand for such stones. There are different pricing influencers for both colored gemstones, and for diamonds. The pricing on colored stones is determined by market supply-and-demand, but diamonds are more intricate. In the addition to the aesthetic and adorning/ornamental purpose of gemstones, there are many proponents of energy medicine who also value gemstones on

6216-457: The rate of 1 mm per month, a typical seven-month growth run produces emerald crystals 7 mm thick. Hydrothermal synthetic emeralds have been attributed to IG Farben , Nacken, Tairus , and others, but the first satisfactory commercial product was that of Johann Lechleitner of Innsbruck , Austria, which appeared on the market in the 1960s. These stones were initially sold under the names "Emerita" and "Symeralds", and they were grown as

6300-531: The same in both. For example, diamonds , rubies , sapphires , and emeralds have been manufactured in labs that possess chemical and physical characteristics identical to the naturally occurring variety. Synthetic (lab created) corundum , including ruby and sapphire, is very common and costs much less than the natural stones. Small synthetic diamonds have been manufactured in large quantities as industrial abrasives , although larger gem-quality synthetic diamonds are becoming available in multiple carats. Whether

6384-426: The same named gemstone can occur in many different colors: sapphires show different shades of blue and pink and "fancy sapphires" exhibit a whole range of other colors from yellow to orange-pink, the latter called " padparadscha sapphire ". This difference in color is based on the atomic structure of the stone. Although the different stones formally have the same chemical composition and structure, they are not exactly

6468-492: The same. Every now and then an atom is replaced by a completely different atom, sometimes as few as one in a million atoms. These so-called impurities are sufficient to absorb certain colors and leave the other colors unaffected. For example, beryl , which is colorless in its pure mineral form, becomes emerald with chromium impurities. If manganese is added instead of chromium , beryl becomes pink morganite . With iron, it becomes aquamarine. Some gemstone treatments make use of

6552-404: The stone's color, luster and other surface properties as opposed to internal reflection properties like brilliance. Grinding wheels and polishing agents are used to grind, shape, and polish the smooth dome shape of the stones. Gems that are transparent are normally faceted, a method that shows the optical properties of the stone's interior to its best advantage by maximizing reflected light which

6636-524: The synthetic stone. Synthetics are made free of common naturally occurring impurities that reduce gem clarity or color unless intentionally added in order to provide a more drab, natural appearance, or to deceive an assayer. On the other hand, synthetics often show flaws not seen in natural stones, such as minute particles of corroded metal from lab trays used during synthesis. Some gemstones are more difficult to synthesize than others and not all stones are commercially viable to attempt to synthesize. These are

6720-419: 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, while others are not accepted most commonly because the gem color is unstable and may revert to the original tone. Before the innovation of modern-day tools, thousands of years ago, people were recorded to use a variety of techniques to treat and enhance gemstones. Some of

6804-461: The world, the industry of coloured gemstones (i.e. anything other than diamonds) is currently estimated at US$ 1.55 billion as of 2023 and is projected to steadily increase to a value of US$ 4.46 billion by 2033. A gem expert is a gemologist , a gem maker is called a lapidarist or gemcutter ; a diamond cutter is called a diamantaire . The traditional classification in the West, which goes back to

6888-401: Was a less costly method than the best known of the ancient Egyptian practices of removing internal organs for separate preservation in canopic jars . The practice ...called for the injection of cedar oil into body cavities without evisceration . The body was laid in natrum or natron —a fixed alkali —for the prescribed period, after which the cedarwood oil, which had dissolved the soft organs,

6972-411: Was released; and the body, its flesh dissolved by the natron, was reduced to preserved skin and bones. As the Roman naturalist and author Pliny the Elder (23/24 –79 CE) in his encyclopedic work Natural History ( Latin : Naturalis Historia ) describes how aromatic oils are produced through the destructive distillation of pine wood, he also mentions that a similar substance, “cedrium” (cedar oil),

7056-418: Was that of Carroll Chatham , likely involving a lithium vanadate flux process, as Chatham's emeralds do not have any water and contain traces of vanadate, molybdenum and vanadium. The other large producer of flux emeralds was Pierre Gilson Sr., whose products have been on the market since 1964. Gilson's emeralds are usually grown on natural colorless beryl seeds, which are coated on both sides. Growth occurs at

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