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92-442: The story is centered around a young man named Rygart Arrow, a resident of a world where people can use "magic". This magic is the ability to control and empower quartz , doing many things from creating light to operating machinery to riding giant mecha called 'Golems'. Rygart, however, is one of the few exceptions; as an "un-sorcerer", he cannot utilize quartz, making many aspects of life difficult as well as being looked down upon by

184-473: A druse (a layer of crystals lining a void), of which quartz geodes are particularly fine examples. The crystals are attached at one end to the enclosing rock, and only one termination pyramid is present. However, doubly terminated crystals do occur where they develop freely without attachment, for instance, within gypsum . α-quartz crystallizes in the trigonal crystal system, space group P 3 1 21 or P 3 2 21 (space group 152 or 154 resp.) depending on

276-560: A pressure cooker . However, the quality and size of the crystals that were produced by these early efforts were poor. Elemental impurity incorporation strongly influences the ability to process and utilize quartz. Naturally occurring quartz crystals of extremely high purity, necessary for the crucibles and other equipment used for growing silicon wafers in the semiconductor industry, are expensive and rare. These high-purity quartz are defined as containing less than 50 ppm of impurity elements. A major mining location for high purity quartz

368-663: A burial context, such as Newgrange or Carrowmore in Ireland . Quartz was also used in Prehistoric Ireland , as well as many other countries, for stone tools ; both vein quartz and rock crystal were knapped as part of the lithic technology of the prehistoric peoples. While jade has been since earliest times the most prized semi-precious stone for carving in East Asia and Pre-Columbian America, in Europe and

460-487: A defining constituent of granite and other felsic igneous rocks . It is very common in sedimentary rocks such as sandstone and shale . It is a common constituent of schist , gneiss , quartzite and other metamorphic rocks . Quartz has the lowest potential for weathering in the Goldich dissolution series and consequently it is very common as a residual mineral in stream sediments and residual soils . Generally

552-584: A high presence of quartz suggests a " mature " rock, since it indicates the rock has been heavily reworked and quartz was the primary mineral that endured heavy weathering. While the majority of quartz crystallizes from molten magma , quartz also chemically precipitates from hot hydrothermal veins as gangue , sometimes with ore minerals like gold, silver and copper. Large crystals of quartz are found in magmatic pegmatites . Well-formed crystals may reach several meters in length and weigh hundreds of kilograms. The largest documented single crystal of quartz

644-572: A natural feel. However, any inclusion of lead or lead solder will give a British Assay office (the body which gives U.K. jewellery its stamp of approval, the Hallmark ) the right to destroy the piece, however, it is very rare for the assay office to do so. Beads are frequently used in jewellery. These may be made of glass, gemstones, metal, wood , shells, clay and polymer clay. Beaded jewellery commonly encompasses necklaces , bracelets , earrings , belts and rings . Beads may be large or small;

736-938: A responsible and modern alternative to mined diamonds. Retailers are responding to this trend by expanding their offerings of lab-grown diamond jewellery, further solidifying their place in the market. Many precious and semiprecious stones are used for jewellery. Among them are: Some gemstones (like pearls, coral, and amber) are classified as organic, meaning that they are produced by living organisms. Others are inorganic, meaning that they are generally composed of and arise from minerals. Some gems, for example, amethyst , have become less valued as methods of extracting and importing them have progressed. Some man-made gems can serve in place of natural gems, such as cubic zirconia , which can be used in place of diamonds. For platinum , gold , and silver jewellery, there are many techniques to create finishes. The most common are high-polish, satin/matte, brushed , and hammered. High-polished jewellery

828-448: A ring can be classified: prong, bezel and tension setting. Synthetic diamonds, also referred to as lab-grown diamonds, are created using advanced technological processes such as High-Pressure High-Temperature (HPHT) and Chemical Vapor Deposition (CVD) . These methods result in diamonds that are chemically and physically identical to natural diamonds , offering the same brilliance and durability. The popularity of synthetic diamonds in

920-602: A rounded steel hammer and hammering the jewellery to give it a wavy texture . Some jewellery is plated to give it a shiny, reflective look or to achieve a desired colour. Sterling silver jewellery may be plated with a thin layer of 0.999 fine silver (a process known as flashing) or plated with rhodium or gold. Base metal costume jewellery may also be plated with silver, gold, or rhodium for a more attractive finish. Jewellery has been used to denote status. In ancient Rome, only certain ranks could wear rings and later, sumptuary laws dictated who could wear what type of jewellery. This

1012-574: A small Brazilian mine, but it is also seen in Lower Silesia in Poland . Naturally occurring prasiolite is also found in the Thunder Bay area of Canada . Quartz crystals have piezoelectric properties; they develop an electric potential upon the application of mechanical stress . Quartz's piezoelectric properties were discovered by Jacques and Pierre Curie in 1880. Quartz is

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1104-475: A status symbol, for its material properties, its patterns, or for meaningful symbols. Jewellery has been made to adorn nearly every body part, from hairpins to toe rings , and even genital jewellery . In modern European culture the amount worn by adult males is relatively low compared with other cultures and other periods in European culture. The word jewellery itself is derived from the word jewel , which

1196-573: A stone bracelet and marble ring are attributed to a similar age. Later, the European early modern humans had crude necklaces and bracelets of bone, teeth, berries, and stone hung on pieces of string or animal sinew , or pieces of carved bone used to secure clothing together. In some cases, jewellery had shell or mother-of-pearl pieces. A decorated engraved pendant (the Star Carr Pendant ) dating to around 11,000 BC, and thought to be

1288-437: A submicroscopic distribution of colloidal ferric hydroxide impurities. Natural citrines are rare; most commercial citrines are heat-treated amethysts or smoky quartzes . However, a heat-treated amethyst will have small lines in the crystal, as opposed to a natural citrine's cloudy or smoky appearance. It is nearly impossible to differentiate between cut citrine and yellow topaz visually, but they differ in hardness . Brazil

1380-680: A superstition that it would bring prosperity. Citrine was first appreciated as a golden-yellow gemstone in Greece between 300 and 150 BC, during the Hellenistic Age . Yellow quartz was used prior to that to decorate jewelry and tools but it was not highly sought after. Milk quartz or milky quartz is the most common variety of crystalline quartz. The white color is caused by minute fluid inclusions of gas, liquid, or both, trapped during crystal formation, making it of little value for optical and quality gemstone applications. Rose quartz

1472-461: A two-to-one margin. In French and a few other European languages the equivalent term, joaillerie , may also cover decorated metalwork in precious metal such as objets d'art and church items, not just objects worn on the person. Humans have used jewellery for a number of different reasons: Most cultures at some point have had a practice of keeping large amounts of wealth stored in the form of jewellery. Numerous cultures store wedding dowries in

1564-556: A war zone and sold to finance an insurgency . The British crown jewels contain the Cullinan Diamond , part of the largest gem-quality rough diamond ever found (1905), at 3,106.75 carats (621.35 g). Now popular in engagement rings , this usage dates back to the marriage of Maximilian I to Mary of Burgundy in 1477. A popular style is the diamond solitaire, which features a single large diamond mounted prominently. Within solitaire, there are three categories in which

1656-400: A woman's death it was sold at the souk and recycled or sold to passers-by. Islamic jewellery from before the 19th century is thus exceedingly rare. The history of jewellery is long and goes back many years, with many different uses among different cultures. It has endured for thousands of years and has provided various insights into how ancient cultures worked. The earliest known Jewellery

1748-542: Is a form of quartz that ranges from a bright vivid violet to a dark or dull lavender shade. The world's largest deposits of amethysts can be found in Brazil, Mexico, Uruguay, Russia, France, Namibia, and Morocco. Sometimes amethyst and citrine are found growing in the same crystal. It is then referred to as ametrine . Amethyst derives its color from traces of iron in its structure. Blue quartz contains inclusions of fibrous magnesio-riebeckite or crocidolite . Inclusions of

1840-401: Is a hard, crystalline mineral composed of silica ( silicon dioxide ). The atoms are linked in a continuous framework of SiO 4 silicon–oxygen tetrahedra , with each oxygen being shared between two tetrahedra, giving an overall chemical formula of SiO 2 . Quartz is, therefore, classified structurally as a framework silicate mineral and compositionally as an oxide mineral . Quartz is

1932-419: Is a monoclinic polymorph. Lechatelierite is an amorphous silica glass SiO 2 which is formed by lightning strikes in quartz sand . As quartz is a form of silica, it is a possible cause for concern in various workplaces. Cutting, grinding, chipping, sanding, drilling, and polishing natural and manufactured stone products can release hazardous levels of very small, crystalline silica dust particles into

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2024-463: Is a primary identifier for the macrocrystalline varieties. Pure quartz, traditionally called rock crystal or clear quartz, is colorless and transparent or translucent and has often been used for hardstone carvings , such as the Lothair Crystal . Common colored varieties include citrine, rose quartz, amethyst, smoky quartz, milky quartz, and others. These color differentiations arise from

2116-400: Is a type of quartz that exhibits a pale pink to rose red hue. The color is usually considered as due to trace amounts of titanium , iron , or manganese in the material. Some rose quartz contains microscopic rutile needles that produce asterism in transmitted light. Recent X-ray diffraction studies suggest that the color is due to thin microscopic fibers of possibly dumortierite within

2208-460: Is also very popular in many African and indigenous North American cultures. Silversmiths , goldsmiths , and lapidaries use methods including forging , casting , soldering or welding , cutting, carving and "cold-joining" (using adhesives , staples and rivets to assemble parts). Diamonds were first mined in India . Pliny may have mentioned them, although there is some debate as to

2300-523: Is often twinned , synthetic quartz is produced for use in industry. Large, flawless, single crystals are synthesized in an autoclave via the hydrothermal process . Like other crystals, quartz may be coated with metal vapors to give it an attractive sheen. Quartz is the most common material identified as the mystical substance maban in Australian Aboriginal mythology . It is found regularly in passage tomb cemeteries in Europe in

2392-660: Is the 'Gold Olive Wreath' (4th century BC), which is modeled on the type of wreath given as a prize for winners in athletic competitions like the Olympic Games. Jewellery dating from 600 to 475 BC is not well represented in the archaeological record, but after the Persian wars the quantity of jewellery again became more plentiful. One particularly popular type of design at this time was a bracelet decorated with snake and animal-heads Because these bracelets used considerably more metal, many examples were made from bronze. By 300 BC,

2484-729: Is the Spruce Pine Gem Mine in Spruce Pine, North Carolina , United States. Quartz may also be found in Caldoveiro Peak , in Asturias , Spain. By the 1930s, the electronics industry had become dependent on quartz crystals. The only source of suitable crystals was Brazil; however, World War II disrupted the supplies from Brazil, so nations attempted to synthesize quartz on a commercial scale. German mineralogist Richard Nacken (1884–1971) achieved some success during

2576-475: Is the leading producer of citrine, with much of its production coming from the state of Rio Grande do Sul . The name is derived from the Latin word citrina which means "yellow" and is also the origin of the word " citron ". Sometimes citrine and amethyst can be found together in the same crystal, which is then referred to as ametrine . Citrine has been referred to as the "merchant's stone" or "money stone", due to

2668-419: Is the most common and gives the metal a highly reflective, shiny look. Satin, or matte finish reduces the shine and reflection of the jewellery, and this is commonly used to accentuate gemstones such as diamonds . Brushed finishes give the jewellery a textured look and are created by brushing a material (similar to sandpaper) against the metal, leaving "brush strokes". Hammered finishes are typically created using

2760-412: Is used for very accurate measurements of very small mass changes in the quartz crystal microbalance and in thin-film thickness monitors . Almost all the industrial demand for quartz crystal (used primarily in electronics) is met with synthetic quartz produced by the hydrothermal process. However, synthetic crystals are less prized for use as gemstones. The popularity of crystal healing has increased

2852-423: Is usually sterling silver , or 92.5% fine silver. In costume jewellery , stainless steel findings are sometimes used. Other commonly used materials include glass , such as fused-glass or enamel ; wood , often carved or turned; shells and other natural animal substances such as bone and ivory ; natural clay ; polymer clay ; Hemp and other twines have been used as well to create jewellery that has more of

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2944-677: The Royal Cemetery of Ur , where hundreds of burials dating 2900–2300 BC were unearthed; tombs such as that of Puabi contained a multitude of artefacts in gold, silver, and semi-precious stones, such as lapis lazuli crowns embellished with gold figurines, close-fitting collar necklaces, and jewel-headed pins. In Assyria , men and women both wore extensive amounts of jewellery, including amulets , ankle bracelets, heavy multi-strand necklaces, and cylinder seals . Jewellery in Mesopotamia tended to be manufactured from thin metal leaf and

3036-524: The hexagonal crystal system above 573 °C (846 K; 1,063 °F). The ideal crystal shape is a six-sided prism terminating with six-sided pyramid-like rhombohedrons at each end. In nature, quartz crystals are often twinned (with twin right-handed and left-handed quartz crystals), distorted, or so intergrown with adjacent crystals of quartz or other minerals as to only show part of this shape, or to lack obvious crystal faces altogether and appear massive . Well-formed crystals typically form as

3128-879: The 14th century in Middle High German and in East Central German and which came from the Polish dialect term twardy , which corresponds to the Czech term tvrdý ("hard"). Some sources, however, attribute the word's origin to the Saxon word Querkluftertz , meaning cross-vein ore . The Ancient Greeks referred to quartz as κρύσταλλος ( krustallos ) derived from the Ancient Greek κρύος ( kruos ) meaning "icy cold", because some philosophers (including Theophrastus ) understood

3220-620: The 1930s and 1940s. After the war, many laboratories attempted to grow large quartz crystals. In the United States, the U.S. Army Signal Corps contracted with Bell Laboratories and with the Brush Development Company of Cleveland, Ohio to synthesize crystals following Nacken's lead. (Prior to World War II, Brush Development produced piezoelectric crystals for record players.) By 1948, Brush Development had grown crystals that were 1.5 inches (3.8 cm) in diameter,

3312-724: The Berber cultures is a style of traditional jewellery worn by women and girls in the rural areas of the Maghreb region in North Africa inhabited by indigenous Berber people (in Berber language : Amazigh, Imazighen , pl). Following long social and cultural traditions, the silversmiths of different ethnic Berber groups of Morocco, Algeria and neighbouring countries created intricate jewellery to adorn their women and that formed part of their ethnic identity . Traditional Berber jewellery

3404-457: The Earth's crust exposed to high temperatures, thereby damaging materials containing quartz and degrading their physical and mechanical properties. Although many of the varietal names historically arose from the color of the mineral, current scientific naming schemes refer primarily to the microstructure of the mineral. Color is a secondary identifier for the cryptocrystalline minerals, although it

3496-457: The Gods. They worked two styles of pieces: cast pieces and pieces hammered out of sheet metal. Fewer pieces of cast jewellery have been recovered. It was made by casting the metal onto two stone or clay moulds. The two-halves were then joined, and wax , followed by molten metal, was placed in the centre. This technique had been practised since the late Bronze Age . The more common form of jewellery

3588-655: The Great conquered part of it. In earlier designs, other European influences can also be detected. When Roman rule came to Greece, no change in jewellery designs was detected. However, by 27 BC, Greek designs were heavily influenced by the Roman culture. That is not to say that indigenous design did not thrive. Numerous polychrome butterfly pendants on silver foxtail chains, dating from the 1st century, have been found near Olbia , with only one example ever found anywhere else. Gorgons, pomegranates, acorns, lotus flowers and palms were

3680-566: The Greeks had mastered making coloured jewellery and using amethysts , pearl , and emeralds . Also, the first signs of cameos appeared, with the Greeks creating them from Indian Sardonyx , a striped brown pink and cream agate stone. Greek jewellery was often simpler than in other cultures, with simple designs and workmanship. However, as time progressed, the designs grew in complexity and different materials were soon used. Jewellery in Greece

3772-521: The Kurgan settlement of Yunatsite near Pazardzhik , the golden treasure Sakar, as well as beads and gold jewellery found in the Kurgan settlement of Provadia – Solnitsata ("salt pit"). However, Varna gold is most often called the oldest since this treasure is the largest and most diverse. By approximately 5,000 years ago, jewellery-making had become a significant craft in the cities of Mesopotamia . The most significant archaeological evidence comes from

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3864-466: The Middle East the different varieties of quartz were the most commonly used for the various types of jewelry and hardstone carving , including engraved gems and cameo gems , rock crystal vases , and extravagant vessels. The tradition continued to produce objects that were very highly valued until the mid-19th century, when it largely fell from fashion except in jewelry. Cameo technique exploits

3956-580: The Museum of Ancient History in Lower Austria revealed that they had found a grave of a female jewellery worker – forcing archaeologists to take a fresh look at prehistoric gender roles after it appeared to be that of a female fine metal worker – a profession that was previously thought to have been carried out exclusively by men. The first signs of established jewellery making in Ancient Egypt

4048-561: The Mycenaean period, but unfortunately this skill was lost at the end of the Bronze Age. The forms and shapes of jewellery in ancient Greece such as the armring (13th century BC), brooch (10th century BC) and pins (7th century BC), have varied widely since the Bronze Age as well. Other forms of jewellery include wreaths, earrings, necklace and bracelets. A good example of the high quality that gold working techniques could achieve in Greece

4140-564: The Shounen web manga anthologies Shonen Blood in October and November 2006 issues and FC Blood from January 1, 2007 to February 8, 2012, and in the Seinen manga anthology Comic Meteo since July 25, 2012. The chapters have been published into tankōbon volumes since April 10, 2007. 20 tankōbon volumes with 104 chapters were released and the manga concluded in October 2022. CMX released

4232-448: The U.S. featured a double-ring ceremony, up from 15% in the 1920s. Some religions have specific rules or traditions surrounding jewellery (or even prohibiting it) and many religions have edicts against excessive display. Islam, for instance, considers the wearing of gold by men as Haraam . The majority of Islamic jewellery was in the form of bridal dowries , and traditionally was not handed down from generation to generation; instead, on

4324-830: The Western practice of married people wearing wedding rings). Wearing of amulets and devotional medals to provide protection or to ward off evil is common in some cultures. These may take the form of symbols (such as the ankh ), stones, plants, animals, body parts (such as the Khamsa ), or glyphs (such as stylised versions of the Throne Verse in Islamic art ). In creating jewellery, gemstones , coins , or other precious items are often used, and they are typically set into precious metals . Platinum alloys range from 900 (90% pure) to 950 (95% pure). The silver used in jewellery

4416-441: The air that workers breathe. Crystalline silica of respirable size is a recognized human carcinogen and may lead to other diseases of the lungs such as silicosis and pulmonary fibrosis . Not all varieties of quartz are naturally occurring. Some clear quartz crystals can be treated using heat or gamma-irradiation to induce color where it would not otherwise have occurred naturally. Susceptibility to such treatments depends on

4508-407: The bands of color in onyx and other varieties. Efforts to synthesize quartz began in the mid-nineteenth century as scientists attempted to create minerals under laboratory conditions that mimicked the conditions in which the minerals formed in nature: German geologist Karl Emil von Schafhäutl (1803–1890) was the first person to synthesize quartz when in 1845 he created microscopic quartz crystals in

4600-469: The body or the clothes. From a western perspective, the term is restricted to durable ornaments , excluding flowers for example. For many centuries metal such as gold often combined with gemstones , has been the normal material for jewellery, but other materials such as glass, shells and other plant materials may be used. Jewellery is one of the oldest types of archaeological artefact – with 100,000-year-old beads made from Nassarius shells thought to be

4692-444: The chirality. Above 573 °C (846 K; 1,063 °F), α-quartz in P 3 1 21 becomes the more symmetric hexagonal P 6 4 22 (space group 181), and α-quartz in P 3 2 21 goes to space group P 6 2 22 (no. 180). These space groups are truly chiral (they each belong to the 11 enantiomorphous pairs). Both α-quartz and β-quartz are examples of chiral crystal structures composed of achiral building blocks (SiO 4 tetrahedra in

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4784-466: The crystal structure. Prase is a green variety of quartz. The green color is caused by inclusions of amphibole . Prasiolite , also known as vermarine , is a variety of quartz that is green in color. The green is caused by iron ions. It is a rare mineral in nature and is typically found with amethyst; most "prasiolite" is not natural – it has been artificially produced by heating of amethyst. Since 1950 , almost all natural prasiolite has come from

4876-433: The crystals. Tridymite and cristobalite are high-temperature polymorphs of SiO 2 that occur in high-silica volcanic rocks. Coesite is a denser polymorph of SiO 2 found in some meteorite impact sites and in metamorphic rocks formed at pressures greater than those typical of the Earth's crust. Stishovite is a yet denser and higher-pressure polymorph of SiO 2 found in some meteorite impact sites. Moganite

4968-482: The demand for natural quartz crystals, which are now often mined in developing countries using primitive mining methods, sometimes involving child labor . Jewellery Jewellery (or jewelry in American English ) consists of decorative items worn for personal adornment such as brooches , rings , necklaces , earrings , pendants , bracelets , and cufflinks . Jewellery may be attached to

5060-470: The exact nature of the stone he referred to as Adamas . In 2005, Australia , Botswana , Russia and Canada ranked among the primary sources of gemstone diamond production. There are negative consequences of the diamond trade in certain areas. Diamonds mined during the recent civil wars in Angola , Ivory Coast , Sierra Leone , and other nations have been labeled as blood diamonds when they are mined in

5152-567: The films mostly follow the manga story, for episode six, the animators deviated from the manga to end the story with their own plot. The Broken Blade films have been adapted and edited into a 12-episode anime series by Production I.G and XEBEC , including scenes never featured in the original movies. The series was aired between April and June 2014 on Tokyo MX and BS11 stations in Japan. Both OP and ending themes were performed by both Sayaka Sasaki and Aira Yuhki . Quartz Quartz

5244-504: The first three volumes of the series in English. The films were chief directed by Tetsurō Amino , directed by Nobuyoshi Habara and produced by Production I.G and XEBEC . The films' opening theme is "Fate", performed by Kokia and closing theme song for the first five movies are "SERIOUS-AGE" by Faylan while the closing theme song for the sixth movie is "Nageki no Oto" ( 嘆きの音 , The Wailing Sound ) , also performed by Kokia. While

5336-567: The five fingers of the hand and is traditionally believed both by Muslims as well as Jewish people to protect against the evil eye . The oldest gold jewellery in the world is dating from 4,600 BC to 4,200 BC and was discovered in Europe, at the site of Varna Necropolis , near the Black Sea coast in Bulgaria . Several prehistoric Bulgarian finds are considered no less old – the golden treasures of Hotnitsa, Durankulak , artifacts from

5428-439: The form of jewellery or make jewellery as a means to store or display coins. Alternatively, jewellery has been used as a currency or trade good to buy and sell. an example being the use of slave beads . Many items of jewellery, such as brooches and buckles , originated as purely functional items, but evolved into decorative items as their functional requirement diminished. Similarly, Tiffany & Co . produced inkwells in

5520-442: The hands. This idea persisted until at least the 17th century. He also knew of the ability of quartz to split light into a spectrum . In the 17th century, Nicolas Steno 's study of quartz paved the way for modern crystallography . He discovered that regardless of a quartz crystal's size or shape, its long prism faces always joined at a perfect 60° angle. Quartz belongs to the trigonal crystal system at room temperature, and to

5612-437: The impurities of phosphate and aluminium that formed crystalline rose quartz, unlike the iron and microscopic dumortierite fibers that formed rose quartz. Smoky quartz is a gray, translucent version of quartz. It ranges in clarity from almost complete transparency to a brownish-gray crystal that is almost opaque. Some can also be black. The translucency results from natural irradiation acting on minute traces of aluminum in

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5704-554: The jewellery had significance. Green, for example, symbolised fertility. Lapis lazuli and silver had to be imported from beyond the country's borders. Egyptian designs were most common in Phoenician jewellery. Also, ancient Turkish designs found in Persian jewellery suggest that trade between the Middle East and Europe was not uncommon. Women wore elaborate gold and silver pieces that were used in ceremonies. Jewellery of

5796-465: The jewellery market has increased significantly due to several factors. Their typically lower price compared to natural diamonds makes them an appealing choice for many consumers. Additionally, the ethical implications of synthetic diamonds have garnered attention, particularly their potential to eliminate the risks associated with conflict diamonds , which are mined in war zones and often used to finance armed conflict. From an environmental perspective,

5888-452: The largest at that time. By the 1950s, hydrothermal synthesis techniques were producing synthetic quartz crystals on an industrial scale, and today virtually all the quartz crystal used in the modern electronics industry is synthetic. An early use of the piezoelectricity of quartz crystals was in phonograph pickups. One of the most common piezoelectric uses of quartz today is as a crystal oscillator . The quartz oscillator or resonator

5980-530: The late 19th and early 20th centuries, skillfully combining materials like enamel and fine metals, reflecting the same craftsmanship seen in their jewellery collections. These inkwells were not only practical but also artistic in design. Jewellery can symbolise group membership (as in the case, of the Christian crucifix or the Jewish Star of David ) or status (as in the case of chains of office , or

6072-517: The location from which the quartz was mined. Prasiolite, an olive colored material, is produced by heat treatment; natural prasiolite has also been observed in Lower Silesia in Poland. Although citrine occurs naturally, the majority is the result of heat-treating amethyst or smoky quartz. Carnelian has been heat-treated to deepen its color since prehistoric times. Because natural quartz

6164-421: The mineral dumortierite within quartz pieces often result in silky-appearing splotches with a blue hue. Shades of purple or gray sometimes also are present. "Dumortierite quartz" (sometimes called "blue quartz") will sometimes feature contrasting light and dark color zones across the material. "Blue quartz" is a minor gemstone. Citrine is a variety of quartz whose color ranges from pale yellow to brown due to

6256-571: The mineral to be a form of supercooled ice. Today, the term rock crystal is sometimes used as an alternative name for transparent coarsely crystalline quartz. Roman naturalist Pliny the Elder believed quartz to be water ice , permanently frozen after great lengths of time. He supported this idea by saying that quartz is found near glaciers in the Alps, but not on volcanic mountains, and that large quartz crystals were fashioned into spheres to cool

6348-501: The most commonly used minerals in the making of jewelry and hardstone carvings , especially in Europe and Asia. Quartz is the mineral defining the value of 7 on the Mohs scale of hardness , a qualitative scratch method for determining the hardness of a material to abrasion. The word "quartz" is derived from the German word Quarz , which had the same form in the first half of

6440-522: The oldest Mesolithic art in Britain, was found at the site of Star Carr in North Yorkshire in 2015. In southern Russia , carved bracelets made of mammoth tusk have been found. The Venus of Hohle Fels features a perforation at the top, showing that it was intended to be worn as a pendant . Around seven thousand years ago, the first sign of copper jewellery was seen. In October 2012,

6532-602: The oldest known jewellery. The basic forms of jewellery vary between cultures but are often extremely long-lived; in European cultures the most common forms of jewellery listed above have persisted since ancient times, while other forms such as adornments for the nose or ankle, important in other cultures, are much less common. Jewellery may be made from a wide range of materials. Gemstones and similar materials such as amber and coral , precious metals , beads , and shells have been widely used, and enamel has often been important. In most cultures jewellery can be understood as

6624-494: The presence of impurities which change the molecular orbitals, causing some electronic transitions to take place in the visible spectrum causing colors. The most important distinction between types of quartz is that of macrocrystalline (individual crystals visible to the unaided eye) and the microcrystalline or cryptocrystalline varieties ( aggregates of crystals visible only under high magnification). The cryptocrystalline varieties are either translucent or mostly opaque, while

6716-403: The present case). The transformation between α- and β-quartz only involves a comparatively minor rotation of the tetrahedra with respect to one another, without a change in the way they are linked. However, there is a significant change in volume during this transition, and this can result in significant microfracturing in ceramics during firing, in ornamental stone after a fire and in rocks of

6808-505: The production of synthetic diamonds generally has a smaller ecological footprint than traditional diamond mining , which can result in extensive land degradation and habitat destruction. While lab-grown diamonds do require energy for their production, many companies are actively adopting renewable energy sources to mitigate their environmental impact. As consumer preferences evolve, particularly among younger generations who prioritize sustainability, synthetic diamonds are increasingly seen as

6900-510: The quartz. Additionally, there is a rare type of pink quartz (also frequently called crystalline rose quartz) with color that is thought to be caused by trace amounts of phosphate or aluminium . The color in crystals is apparently photosensitive and subject to fading. The first crystals were found in a pegmatite found near Rumford , Maine , US, and in Minas Gerais , Brazil. The crystals found are more transparent and euhedral, due to

6992-596: The rest of society. Despite this, in his youth he managed to befriend Hodr and Sigyn, the future King and Queen of the Krisna Kingdom; and Zess, the younger brother of the Secretary of War of the Athens Commonwealth. Years later, Rygart is reunited with Hodr and Sigyn where he learns the Athens Commonwealth has begun an invasion of Krisna. Rygart is also shocked to learn that Zess is leading one of

7084-682: The second most abundant mineral in Earth 's continental crust , behind feldspar . Quartz exists in two forms, the normal α-quartz and the high-temperature β-quartz, both of which are chiral . The transformation from α-quartz to β-quartz takes place abruptly at 573 °C (846 K; 1,063 °F). Since the transformation is accompanied by a significant change in volume, it can easily induce microfracturing of ceramics or rocks passing through this temperature threshold. There are many different varieties of quartz, several of which are classified as gemstones . Since antiquity, varieties of quartz have been

7176-417: The slang term bling-bling , which refers to the ostentatious display of jewellery by men or women. Conversely, the jewellery industry in the early 20th century launched a campaign to popularise wedding rings for men, which caught on, as well as engagement rings for men, which did not, go so far as to create a false history and claim that the practice had medieval roots. By the mid-1940s, 85% of weddings in

7268-482: The smallest type of beads used are known as seed beads , these are the beads used for the "woven" style of beaded jewellery. Seed beads are also used in an embroidery technique where they are sewn onto fabric backings to create broad collar neck pieces and beaded bracelets. Bead embroidery, a popular type of handwork during the Victorian era , is enjoying a renaissance in modern jewellery making. Beading, or beadwork,

7360-573: The strike forces. While at the capital, Rygart discovers that he has the ability to pilot a recently discovered ancient Golem which cannot be piloted by magic users. Despite its ancient origins, the golem possesses capabilities and systems far more advanced than the current Golems, and could be key to turning the tide of battle. While hesitant at first, Rygart soon gets involved in the war between Krisna and Athens, in an attempt to save Hodr, Sigyn, and even Zess. Written and illustrated by Yunosuke Yoshinaga, Broken Blade has been serialized by Flex Comix in

7452-584: The trade and manufacture of jewellery have also been unearthed throughout Mesopotamian archaeological sites. One record in the Mari royal archives, for example, gives the composition of various items of jewellery: The Greeks started using gold and gems in jewellery in 1600 BC, although beads shaped as shells and animals were produced widely in earlier times. Around 1500 BC, the main techniques of working gold in Greece included casting, twisting bars, and making wire. Many of these sophisticated techniques were popular in

7544-414: The transparent varieties tend to be macrocrystalline. Chalcedony is a cryptocrystalline form of silica consisting of fine intergrowths of both quartz, and its monoclinic polymorph moganite . Other opaque gemstone varieties of quartz, or mixed rocks including quartz, often including contrasting bands or patterns of color, are agate , carnelian or sard, onyx , heliotrope , and jasper . Amethyst

7636-590: Was anglicised from the Old French " jouel ", and beyond that, to the Latin word " jocale ", meaning plaything. In British English , Indian English , New Zealand English , Hiberno-English , Australian English , and South African English it is spelled jewellery. At the same time, the spelling is jewelry in American English . Both are used in Canadian English . However, jewellery prevails by

7728-518: Was actually created not by modern humans ( Homo sapiens ) but by Neanderthal living in Europe. Specifically, perforated beads made from small seashells have been found dating to 115,000 years ago in the Cueva de los Aviones, a cave along the southeast coast of Spain. Later in Kenya, at Enkapune Ya Muto , beads made from perforated ostrich eggshells have been dated to more than 40,000 years ago. In Russia,

7820-465: Was also based on the rank of the citizens of that time. Cultural dictates have also played a significant role. For example, the wearing of earrings by Western men was considered effeminate in the 19th century and early 20th century. More recently, the display of body jewellery, such as piercings , has become a mark of acceptance or seen as a badge of courage within some groups but is completely rejected in others. Likewise, hip hop culture has popularised

7912-484: Was around 3,000–5,000 years ago. The Egyptians preferred the luxury, rarity, and workability of gold over other metals. In Predynastic Egypt jewellery soon began to symbolise political and religious power in the community. Although it was worn by wealthy Egyptians in life, it was also worn by them in death, with jewellery commonly placed among grave goods . In conjunction with gold jewellery, Egyptians used coloured glass , along with semi-precious gems. The colour of

8004-420: Was first developed by Walter Guyton Cady in 1921. George Washington Pierce designed and patented quartz crystal oscillators in 1923. The quartz clock is a familiar device using the mineral. Warren Marrison created the first quartz oscillator clock based on the work of Cady and Pierce in 1927. The resonant frequency of a quartz crystal oscillator is changed by mechanically loading it, and this principle

8096-541: Was found near Itapore , Goiaz , Brazil; it measured approximately 6.1 m × 1.5 m × 1.5 m (20 ft × 5 ft × 5 ft) and weighed over 39,900 kg (88,000 lb). Quartz is extracted from open pit mines . Miners occasionally use explosives to expose deep pockets of quartz. More frequently, bulldozers and backhoes are used to remove soil and clay and expose quartz veins, which are then worked using hand tools. Care must be taken to avoid sudden temperature changes that may damage

8188-441: Was hardly worn and was mostly used for public appearances or on special occasions. It was frequently given as a gift and was predominantly worn by women to show their wealth, social status, and beauty. The jewellery was often supposed to give the wearer protection from the " evil eye " or endowed the owner with supernatural powers , while others had a religious symbolism. Older pieces of jewellery that have been found were dedicated to

8280-457: Was set with large numbers of brightly coloured stones (chiefly agate, lapis, carnelian, and jasper). Favoured shapes included leaves, spirals, cones, and bunches of grapes. Jewellers created works both for human use and for adorning statues and idols. They employed a wide variety of sophisticated metalworking techniques, such as cloisonné , engraving , fine granulation , and filigree . Extensive and meticulously maintained records pertaining to

8372-491: Was the hammered sheet type. Sheets of metal would be hammered to thickness and then soldered together. The inside of the two sheets would be filled with wax or another liquid to preserve the metal work. Different techniques, such as using a stamp or engraving, were then used to create motifs on the jewellery. Jewels may then be added to hollows or glass poured into special cavities on the surface. The Greeks took much of their designs from outer origins, such as Asia, when Alexander

8464-465: Was usually made of silver and includes elaborate brooches made of triangular plates and pins ( fibula ), originally used as clasps for garments, but also necklaces, bracelets, earrings and similar items. Another major type is the so-called khmissa (local pronunciation of the Arabic word "khamsa" for the number "five"), which is called afus in the Berber language ( Tamazight) . This form represents

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