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43-540: The Afghan Rushan (Rushan is also a separate district in Tajikistan) falls under the administrative rule of Shughnan district, and is referred to as Rushan sub-district (i.e. Rushan Alaqadari). There are about ten sizable and many more smaller villages in the Shughnan district of Afghanistan. These villages include, south to north, Darmarakht, Wiyod, Wiroodhj, Bashor, Vuzh-Pidrudh, Dhishahr, Shidwood, and Tsaghnod. Note;

86-451: A hardness of 9.0 on the Mohs scale of mineral hardness . Among the natural gems, only moissanite and diamond are harder, with diamond having a Mohs hardness of 10.0 and moissanite falling somewhere in between corundum (ruby) and diamond in hardness. Sapphire, ruby, and pure corundum are α-alumina, the most stable form of Al 2 O 3 , in which 3 electrons leave each aluminium ion to join

129-485: A clear stone will command a premium, but a ruby without any needle-like rutile inclusions may indicate that the stone has been treated. Ruby is the traditional birthstone for July and is usually pinker than garnet , although some rhodolite garnets have a similar pinkish hue to most rubies. The world's most valuable ruby to be sold at auction is the Sunrise Ruby , which sold for US$ 34.8 million. Rubies have

172-545: A little chromium at red heat . In 1903, Verneuil announced he could produce synthetic rubies on a commercial scale using this flame fusion process, later also known as the Verneuil process . By 1910, Verneuil's laboratory had expanded into a 30 furnace production facility, with annual gemstone production having reached 1,000 kilograms (2,000 lb) in 1907. Other processes in which synthetic rubies can be produced are through Czochralski's pulling process , flux process, and

215-561: A similar range of gemstones associated with birth, though rather than associating a gem with a birth month, gemstones are associated with celestial bodies . Astrology determines the gemstones most closely associated with and beneficial to a particular individual. For example, in Hinduism, there are nine gemstones related to the Navagraha (celestial forces including the planets, the Sun, and

258-553: Is lead glass filling. Filling the fractures inside the ruby with lead glass (or a similar material) dramatically improves the transparency of the stone, making previously unsuitable rubies fit for applications in jewelry. The process is done in four steps: If a color needs to be added, the glass powder can be "enhanced" with copper or other metal oxides as well as elements such as sodium, calcium, potassium etc. The second heating process can be repeated three to four times, even applying different mixtures. When jewelry containing rubies

301-508: Is a gemstone that represents a person's birth period, usually the month or zodiac sign . Birthstones are often worn as jewelry or a pendant necklace. The first-century historian Josephus believed there was a connection between the twelve stones in Aaron's breastplate (signifying the tribes of Israel, as described in the Book of Exodus ), the twelve months of the year, and the twelve signs of

344-413: Is defined to be red. All other hues of the gem species corundum are called sapphire. Ruby may exhibit a range of secondary hues, including orange, purple, violet, and pink. Because rubies host many inclusions, their clarity is evaluated by the inclusions’ size, number, location, and visibility. Rubies with the highest clarity grades are known as “eye-clean,” because their inclusions are the least visible to

387-710: Is heated (for repairs) it should not be coated with boracic acid or any other substance, as this can etch the surface; it does not have to be "protected" like a diamond. The treatment can be identified by noting bubbles in cavities and fractures using a 10× loupe. In 1837, Gaudin made the first synthetic rubies by fusing potash alum at a high temperature with a little chromium as a pigment. In 1847, Ebelmen made white sapphire by fusing alumina in boric acid. In 1877, Edmond Frémy and industrial glass-maker Charles Feil made crystal corundum from which small stones could be cut. In 1887, Fremy and Auguste Verneuil manufactured artificial ruby by fusing BaF 2 and Al 2 O 3 with

430-514: Is more rainfall than in summer. The average annual temperature in Shighnan is 3.6 °C (38.5 °F). About 782 mm (30.79 in) of precipitation falls annually. Pamiris such as the Shughnis are the main ethnic group of the region. Pamiri languages primarily Shughni are mainly spoken there. Ruby Ruby is a pinkish red to blood-red colored gemstone , a variety of

473-399: Is the most important factor. Color divides into three components: hue , saturation and tone . Hue refers to color as we normally use the term. Transparent gemstones occur in the pure spectral hues of red, orange, yellow, green, blue, violet. In nature, there are rarely pure hues, so when speaking of the hue of a gemstone, we speak of primary and secondary and sometimes tertiary hues. Ruby

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516-485: Is the only country in mainland Europe to have naturally occurring rubies. They can mainly be found around the city of Prilep . Macedonian rubies have a unique raspberry color. A few rubies have been found in the U.S. states of Montana , North Carolina , South Carolina and Wyoming . Spinel , another red gemstone, is sometimes found along with rubies in the same gem gravel or marble. Red spinels may be mistaken for rubies by those lacking experience with gems. However,

559-587: The Black Prince's Ruby in the British Imperial State Crown , are actually spinels . These were once known as "Balas rubies". The quality of a ruby is determined by its color, cut, and clarity, which, along with carat weight, affect its value. The brightest and most valuable shade of red, called blood-red or pigeon blood, commands a large premium over other rubies of similar quality. After color follows clarity: similar to diamonds,

602-626: The Gemological Institute of America starts it in Germany in the 1560s. Modern lists of birthstones have little to do with either the breastplate or the Foundation Stones of Christianity. Tastes, customs, and confusing translations have distanced them from their historical origins, with one author calling the 1912 Kansas list (see below) "nothing but a piece of unfounded salesmanship." Some poems match each month of

645-534: The Gregorian calendar with a birthstone. These are traditional stones of English-speaking societies. Tiffany & Co. published these poems "of unknown author" for the first time in a pamphlet in 1870. In 1912, to standardize birthstones, the (American) National Association of Jewelers (now called Jewelers of America ) met in Kansas and officially adopted a list. The Jewelry Industry Council of America updated

688-760: The hydrothermal process . Most synthetic rubies originate from flame fusion, due to the low costs involved. Synthetic rubies may have no imperfections visible to the naked eye but magnification may reveal curved striae and gas bubbles. The fewer the number and the less obvious the imperfections, the more valuable the ruby is; unless there are no imperfections (i.e., a perfect ruby), in which case it will be suspected of being artificial. Dopants are added to some manufactured rubies so they can be identified as synthetic, but most need gemological testing to determine their origin. Synthetic rubies have technological uses as well as gemological ones. Rods of synthetic ruby are used to make ruby lasers and masers . The first working laser

731-478: The mineral corundum ( aluminium oxide ). Ruby is one of the most popular traditional jewelry gems and is very durable. Other varieties of gem-quality corundum are called sapphires . Ruby is one of the traditional cardinal gems , alongside amethyst , sapphire , emerald , and diamond . The word ruby comes from ruber , Latin for red. The color of a ruby is due to the element chromium . Some gemstones that are popularly or historically called rubies, such as

774-505: The mirs of Shighnan , claimed descent from Alexander the Great . The archaeologist Marc Aurel Stein wrote: "North of Shughnan lies Roshan, ruled usually by relatives of the old chiefs of Shughnan... there is no proof, however, to their genealogical claims." [2] In 1829 the Mirs of Shughnan were forced to pay tribute to Murad Beg of Kunduz. In 1874 Shughnan was subjugated into Afghanistan, but

817-700: The zodiac . Translations and interpretations of the passage in Exodus regarding the breastplate have varied widely, with Josephus himself giving two different lists for the twelve stones. George Frederick Kunz argues that Josephus saw the breastplate of the Second Temple , not the one described in Exodus. St. Jerome , referencing Josephus, said the Foundation Stones of the New Jerusalem ( Revelation 21:19–20) would be appropriate for Christians. In

860-566: The 17th century techniques were developed to color foil red—by burning scarlet wool in the bottom part of the furnace—which was then placed under the imitation stone. Trade terms such as balas ruby for red spinel and rubellite for red tourmaline can mislead unsuspecting buyers. Such terms are therefore discouraged from use by many gemological associations such as the Laboratory Manual Harmonisation Committee (LMHC). Birthstone A birthstone

903-536: The Aappaluttoq mine in Greenland began running. The rubies in Greenland are said to be among the oldest in the world at approximately 3 billion years old. The Aappaluttoq mine in Greenland is located 160 kilometers south of Nuuk, the capital of Greenland. The rubies are traceable from mine to market. The Montepuez ruby mine in northeastern Mozambique is situated on one of the most significant ruby deposits in

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946-517: The Al 2 O 3 crystal. However, the Cr ions are larger and have electron orbitals in different directions than aluminium. The octahedral arrangement of the O ions is distorted, and the energy levels of the different orbitals of those Cr ions are slightly altered because of the directions to the O ions. Those energy differences correspond to absorption in the ultraviolet, violet, and yellow-green regions of

989-937: The International Colored Gemstone Association (ICGA) have adopted the broader definition for ruby which encompasses its lighter shades, including pink. Historically, rubies have been mined in Thailand, in the Pailin and Samlout District of Cambodia , as well as in Afghanistan , Australia , Brazil , Colombia , India , Namibia , Japan , and Scotland. After the Second World War , ruby deposits were found in Madagascar , Mozambique , Nepal, Pakistan, Tajikistan , Tanzania , and Vietnam . The Republic of North Macedonia

1032-515: The Moon), known in Sanskrit as Navaratna (nine gems). At birth, an astrological chart is calculated. Specific stones are recommended to be worn on the body to supposedly ward off potential problems based on the place of these forces in the sky at the exact place and time of birth. While the term "birthday stone" is sometimes used as a synonym for a birthstone, each day of the week is also assigned

1075-503: The United States, a minimum color saturation must be met to be called a ruby; otherwise, the stone will be called a pink sapphire . Drawing a distinction between rubies and pink sapphires is relatively new, having arisen sometime in the 20th century. Often, the distinction between ruby and pink sapphire is not clear and can be debated. As a result of the difficulty and subjectiveness of such distinctions, trade organizations such as

1118-598: The crystal during that time, they can stimulate more fluorescent photons to be emitted in-phase with them, thus strengthening the intensity of that red light. By arranging mirrors or other means to pass emitted light repeatedly through the crystal, a ruby laser in this way produces a very high intensity of coherent red light. All natural rubies have imperfections in them, including color impurities and inclusions of rutile needles known as "silk". Gemologists use these needle inclusions found in natural rubies to distinguish them from synthetics, simulants, or substitutes. Usually,

1161-458: The crystal growth process) to be ten to twenty times less than in the natural gemstones. Theodore Maiman says that "because of the low chromium level in these crystals they display a lighter red color than gemstone ruby and are referred to as pink ruby ." After absorbing short-wavelength light, there is a short interval of time when the crystal lattice of ruby is in an excited state before fluorescence occurs. If 694-nanometer photons pass through

1204-434: The eighth and ninth centuries, religious treatises associating a particular stone with an apostle were written so that "their name would be inscribed on the Foundation Stones, and his virtue." Practice became to keep twelve stones and wear one a month. The custom of wearing a single birthstone is only a few centuries old, though modern authorities differ on dates. Kunz places the custom in eighteenth-century Poland , while

1247-480: The finest red spinels, now heavily sought, can have values approaching all but the finest examples of ruby. The Mogok Valley in Upper Myanmar (Burma) was for centuries the world's main source for rubies. That region has produced some exceptional rubies; however, in recent years few good rubies have been found. In central Myanmar, the area of Mong Hsu began producing rubies during the 1990s and rapidly became

1290-408: The late 1990s, a large supply of low-cost materials caused a sudden surge in supply of heat-treated rubies, leading to a downward pressure on ruby prices. Improvements used include color alteration, improving transparency by dissolving rutile inclusions, healing of fractures (cracks) or even completely filling them. The most common treatment is the application of heat. Most rubies at the lower end of

1333-712: The list in 1952 by adding Alexandrite for June, citrine for November and pink tourmaline for October. They also replaced December's lapis with zircon and switched the primary/alternative gems for March. The American Gem Trade Association added tanzanite as a December birthstone in 2002. In 2016, the American Gem Trade Association and Jewelers of America added spinel as an additional birthstone for August. Britain's National Association of Goldsmiths created its own standardized list of birthstones in 1937. In 2021, Japanese industry associations added ten new types of birthstones. Eastern culture recognizes

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1376-472: The market are heat treated to improve color, remove purple tinge , blue patches, and silk. These heat treatments typically occur around temperatures of 1800 °C (3300 °F). Some rubies undergo a process of low tube heat, when the stone is heated over charcoal of a temperature of about 1300 °C (2400 °F) for 20 to 30 minutes. The silk is partially broken, and the color is improved. Another treatment, which has become more frequent in recent years,

1419-672: The mirs still continues to rule the area until September 1883, when Shughnan was annexed by Abdur Rahman Khan . The area was assigned to Russia by the Durand agreement of 1893. In an 1895 agreement between the British and Russia, Moscow agreed to hand over all districts previously occupied by her on the left bank of the Panj , or upper Oxus, to Afghanistan in exchange for lands on the right hand bank in Darvaz . The Russian-controlled half of Shughnan

1462-445: The naked human eye. Rubies may also have thin, intersecting inclusions called silk. Silk can scatter light, brightening the gem's appearance, and the presence of silk can also show whether a ruby has been previously heat treated, since intense heat will degrade a ruby's silk. Improving the quality of gemstones by treating them is common practice. Some treatments are used in almost all cases and are therefore considered acceptable. During

1505-412: The regular octahedral group of six nearby O ions; in pure corundum this leaves all of the aluminium ions with a very stable configuration of no unpaired electrons or unfilled energy levels, and the crystal is perfectly colorless, and transparent except for flaws. When a chromium atom replaces an occasional aluminium atom, it too loses 3 electrons to become a chromium ion to maintain the charge balance of

1548-415: The rough stone is heated before cutting. These days, almost all rubies are treated in some form, with heat treatment being the most common practice. Untreated rubies of high quality command a large premium. Some rubies show a three-point or six-point asterism or "star". These rubies are cut into cabochons to display the effect properly. Asterisms are best visible with a single-light source and move across

1591-403: The spectrum. If one percent of the aluminium ions are replaced by chromium in ruby, the yellow-green absorption results in a red color for the gem. Additionally, absorption at any of the above wavelengths stimulates fluorescent emission of 694-nanometer-wavelength red light, which adds to its red color and perceived luster . The chromium concentration in artificial rubies can be adjusted (in

1634-491: The stone as the light moves or the stone is rotated. Such effects occur when light is reflected off the "silk" (the structurally oriented rutile needle inclusions) in a certain way. This is one example where inclusions increase the value of a gemstone. Furthermore, rubies can show color changes—though this occurs very rarely—as well as chatoyancy or the "cat's eye" effect. Generally, gemstone-quality corundum in all shades of red, including pink, are called rubies. However, in

1677-578: The village names are given as they appear in the local language. Population of the Afghan district totals approximately 24,000 residents. Some of the bigger villages in the Tajik side of Shughnan include, south to north, Darmarakht, Porshnev, Buni, Sokhcharv, and Rosht Qala. In ancient times the area was known for its ruby mines, which are mentioned in the writings of Marco Polo : In modern times Shughnan and its vassal Roshan were states whose native rulers,

1720-520: The world's main ruby mining area. The most recently found ruby deposit in Myanmar is in Namya (Namyazeik) located in the northern state of Kachin . In Pakistani Kashmir there are vast proven reserves of millions of rubies, worth up to half a billion dollars. However, as of 2017 there was only one mine (at Chitta Katha) due to lack of investment. In Afghanistan , rubies are mined at Jegdalek. In 2017

1763-429: The world, although, rubies were only discovered here for the first time in 2009. In less than a decade, Mozambique has become the world's most productive source for gem-quality ruby. Rubies, as with other gemstones, are graded using criteria known as the four Cs, namely color, cut, clarity and carat weight. Rubies are also evaluated on the basis of their geographic origin. In the evaluation of colored gemstones, color

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1806-485: Was incorporated into the Gorno-Badakhshan oblast in 1925, which was merged into the newly formed Tajikistan in 1929. The people residing in the Shughnan district, both the Tajik side and Afghan side of the border, speak their own language called Shughni (Khughnani). Shighnan has a humid continental climate ( Köppen climate classification Dsb ) with dry, mild summers and cold, snowy winters. In winter there

1849-563: Was made by Theodore H. Maiman in 1960. Maiman used a solid-state light-pumped synthetic ruby to produce red laser light at a wavelength of 694 nanometers (nm). Ruby lasers are still in use. Rubies are also used in applications where high hardness is required such as at wear-exposed locations in mechanical clockworks, or as scanning probe tips in a coordinate measuring machine . Imitation rubies are also marketed. Red spinels , red garnets , and colored glass have been falsely claimed to be rubies. Imitations go back to Roman times and already in

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