Opal chemical composition

Care. Opal is relatively soft, Peruvian opal should be treated with care as it can be scratched by any harder material. Wash in warm soapy (non-detergent) water. 16.50.02: Blue Peruvian Opal is shared under a CC BY-NC-SA license and was authored, remixed, and/or curated by LibreTexts. 16.50.01: Black Opal.

Opal chemical composition. Opal Uses and Purposes. Opals promote a sense of calm security, easing stress and depression, and encouraging one to stop brooding in order to better direct one’s thoughts and energies. They are antidotes to restless thoughts and racing minds that rehash the past or anticipate the future.

Specific gravities are expressed in decimal numbers, for example, 4.00 for corundum, 3.52 for diamond , and 2.72 for quartz. Zircon, one of the densest of all gemstones, may have a specific gravity as high as 4.73! Specific gravity is an important tool in gemstone identification that is useful for the gem buyer as well as the gemologist.

Chemical Formula SiO2·nH2O; Composition Hydrated Silica; WHERE IS OPAL MINED? Where do Opals come from? Well, Australia has been a world-class source for Opal since the mid-1800s, with considerable mining operations in Lightning Ridge, Coober Pedy, Mintabie, Andamooka and others too.Opal is a hydrous silica composed of predominantly silicon dioxide and water. The chemical composition of opal is normally described by the general formula SiO2.nH2O. The formula indicates that opal contains water and the value of ‘n’ is variable so the water content is variable and is known to range widely.Natural Opal Type 1 – is opal presented in one piece in its natural state apart from cutting or polishing and is of substantially homogenous chemical composition. Natural Opal Type 2 – is opal presented in one piece where the opal is naturally attached to the host rock in which it was formed and the host rock is of a different chemical ...General Opal Information : Chemical Formula: SiO2•n(H2O) Composition: Molecular Weight = 87.11 gm Silicon 32.24 % Si 68.98 % SiO 2 Hydrogen 3.47 % H 31.02 % H 2 O Oxygen 64.29 % O _____ _____ 100.00 % 100.00 % = TOTAL OXIDE: Empirical Formula: SiO 2 •1.5(H 2 O) Environment:Opal Uses and Purposes. Opals promote a sense of calm security, easing stress and depression, and encouraging one to stop brooding in order to better direct one’s thoughts and energies. They are antidotes to restless thoughts and racing minds that rehash the past or anticipate the future. Physical and chemical properties. The crystallographic structures of the silica minerals, except stishovite, are three-dimensional arrays of linked tetrahedrons, each consisting of a silicon atom coordinated by four oxygen atoms. The tetrahedrons are usually quite regular, and the silicon-oxygen bond distances are 1.61 ± 0.02 Å.

Specific gravities are expressed in decimal numbers, for example, 4.00 for corundum, 3.52 for diamond , and 2.72 for quartz. Zircon, one of the densest of all gemstones, may have a specific gravity as high as 4.73! Specific gravity is an important tool in gemstone identification that is useful for the gem buyer as well as the gemologist.Physical and chemical properties. The crystallographic structures of the silica minerals, except stishovite, are three-dimensional arrays of linked tetrahedrons, each consisting of a silicon atom coordinated by four oxygen atoms. The tetrahedrons are usually quite regular, and the silicon-oxygen bond distances are 1.61 ± 0.02 Å.Synthetic opals are man-made opals that have the same chemical composition, internal structure, physical properties, and appearance as natural opals. They are often called lab-created opals, lab-grown opals, or cultured opals to indicate their man-made origin. Synthetic opals can exhibit a spectacular play-of-color appearance that often exceeds ...Tendency to chemical cement. Ash: unconsolidated fragments under. 4 mm. Tuff: consolidated ash. Volcanic Breccia: angular fragments over 4 mm. Agglomerate: large proportion (>25%) of bombs. These rocks are classified on the proportions of vitric, crystal (mineral), or lithic material they contain, for example, "vitric lithic ash," or "crystal ...In this post, we reveal everything you need to know about green opal, including its meaning, benefits, properties, types, and uses. Let's get started! Introduction Crystals are ancient precious stones that are making a comeback! The first recorded historical use of crystals dates back to the Ancient Sumerians who lived during the 4th …

1. Chemical Composition. Opal. This gem is made up of tiny silica spheres, formed when silica-rich water enters into the deep voids and cracks present on the earth’s crust. Technically, the opal is a hydrated amorphous form of silica and is classified as a mineraloid. MoonstoneSep 7, 2023 · An opal is a 'gemstone' - that is, a mineral valued for its beauty. Gemstones are most often used in jewellery and examples include diamonds, rubies, emeralds, sapphires, jade, opals and amethysts. Gems generally get their colour because of certain metals contained in the mineral (for example purple amethyst is quartz containing tiny amounts of ... Opal; Chemical composition: SiO 2 +.H 2 O: Crystal system: Amorphous: Hardness: 5- 6 1/2: Refractive index: 1.45 (+.020;-0.080) Specific gravity: 2.15 (+0.07;-0.90) Lustre: …synthetic opal chemical composition: sio2.nh2o+resin Many countries manufacture opals as it is a valuable gemstone, so unfortunately we will be expecting more synthetic opals to come on line. To our knowledge China and Thailand are constantly trying to manufacture new products for this market to catch the unsuspecting opal buyer.

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Common opal is a mineraloid. It is an amorphous silica with a chemical composition of SiO 2. nH 2 O. It has a conchoidal fracture that is characteristic of an amorphous glass. Precious Opal is a mineraloid. The play-of-color in opal is produced when light travels through a three-dimensional array of tiny silica spheres within the material.Iolite (also called Dichroite or Cordierite) is a transparent, violet-blue, light blue, blue, rich blue-violet stone. It is a blue silicate mineral that occurs as crystals or grains in igneous rocks, only as a result of contamination of the magma by aluminous sediment. Its chemical composition is Magnesium Aluminum Silicate (Mg 2 Al 3 O).Results show that the main mineral composition of blue opal is amorphous opal and the vibrational spectra show some peak frequency shifts relative to natural opal. EMPA shows that the main elements of blue opals are Si and Cu, whereas the Uv-Vis spectrum shows a broad band with higher absorption intensity near 742 nm.well as in the chemical composition and IR spectral features, were noted between Mexifire synthetic opals and their natural fire opal counterparts. However ...

About Tanzanite. Found in just one place on earth, tanzanite is a relatively recent discovery. Tiffany & Co named this blue-violet variety of zoisite in honor of Tanzania, where it was first unearthed in 1967. Because the crystals show different colors depending on the viewing direction, cutters can fashion gems with a range of color from ...Physical and chemical properties. The crystallographic structures of the silica minerals, except stishovite, are three-dimensional arrays of linked tetrahedrons, each consisting of a silicon atom coordinated by four oxygen atoms. The tetrahedrons are usually quite regular, and the silicon-oxygen bond distances are 1.61 ± 0.02 Å.These minerals are very similar in chemical composition, crystal structure, physical properties and often in appearance. Members of the group are: turquoise, aheylite, chalcosiderite, faustite, and planerite. Their compositions are listed in the accompanying table. Notice that the members of the turquoise group have very similar chemical ... Synthetic opals are man-made opals that have the same chemical composition, internal structure, physical properties, and appearance as natural opals. They are often called lab-created opals, lab-grown opals, or cultured opals to indicate their man-made origin. Synthetic opals can exhibit a spectacular play-of-color appearance that often exceeds ...Chemical Properties: Composition: Opals are primarily composed of hydrated silicon dioxide (SiO2·nH2O), commonly …Opal definition, a mineral, an amorphous form of silica, SiO2 with some water of hydration, found in many varieties and colors, including a form that is milky white. See more.Apr 17, 2023 ... This is due to the unique chemical composition of opals, which can include trace amounts of impurities such as iron, manganese, and copper.Fire Opal is rare compared to other colors because of its chemical structure and depositional environment. To illustrate, opal stones reflect a red color when white light refracts upon sections of larger silica spheres. And the composition of larger silica spheres in an opal stone is due to a less common depositional environment. About Tanzanite. Found in just one place on earth, tanzanite is a relatively recent discovery. Tiffany & Co named this blue-violet variety of zoisite in honor of Tanzania, where it was first unearthed in 1967. Because the crystals show different colors depending on the viewing direction, cutters can fashion gems with a range of color from ...Lutetium is suitable for radiolabelling of biologically active tracer molecules, with a similar chemical approach as the positron emitter gallium-68, ... SM-3 (Russia). These facilities have been designed specifically to generate high neutron fluxes. Except for FRM-II and OPAL, these reactors are more than 40 years old.

General Opal Information : Chemical Formula: SiO2•n(H2O) Composition: Molecular Weight = 87.11 gm Silicon 32.24 % Si 68.98 % SiO 2 Hydrogen 3.47 % H 31.02 % H 2 O Oxygen 64. ... Opal Image: Images: Opal. Comments: Colorful white opal on a sandstone matrix.

Jun 20, 2023 ... Chemical Composition: What Lies Beneath ... Moonstones are primarily composed of orthoclase feldspar minerals with scattered deposits of albite ...Opal (contains water), with 2 microcrystalline and 2 non-crystalline variants Lechatelierite, Silica Glass ... Because these α-β-transitions are only based on alterations of the angles and the lengths of the chemical bonds, they take place instantaneously. ... Opals differ considerably in their microstructure and composition, their common ...Opal’s Color. The most well-known opals are traditionally classified as black or white, but other base hues include red, purple, and orange. ... However, their chemical compositions vary extensively, resulting in a diverse range of colors due to the presence of distinct elements. Some gems also have an effect called cat’s eye, which often ...Opal is a hydrous silicon dioxide with a chemical composition of SiO2.nH2O in terms of mineralogy. It's amorphous, meaning it doesn't have a crystalline structure or a specific chemical composition (it contains a variable amount of water, as shown by the "n" in its chemical composition).May 29, 2014 · Hardness: 7.5 - 8 on the Mohs scale Chemical Composition: Beryllium aluminum silicate. The beryl family is considered to be one of the most important of gemstone groups. The beryl group is most famous for emerald, a rich green chromium colored variety of precious beryl. Coal is a non-clastic sedimentary rock.They are the fossilized remains of plants and are in flammable black and brownish-black tones. Its main element is carbon, but it can also contain different elements such as hydrogen, sulfur and oxygen. Unlike coal minerals, it does not have a fixed chemical composition and crystal …The early synthesis of opal attempted to produce synthetic opal with this chemical composition, however it is likely that at some stage during the refinement of the manufacturing process that two modifications were made. First, most of the water was removed from the synthesised opal. The second was the introduction of a suitable 'stabilizing ...Physical Properties of Girasol Opal Stone ; Chemical Formula: SiO2 . nH2O ; Chemical Composition: hydrated form of silica ; Crystal System: Amorphous ; Lustre: ...Physical and chemical properties. The crystallographic structures of the silica minerals, except stishovite, are three-dimensional arrays of linked tetrahedrons, each consisting of a silicon atom coordinated by four oxygen atoms. The tetrahedrons are usually quite regular, and the silicon-oxygen bond distances are 1.61 ± 0.02 Å.Chalcedony (/ k æ l ˈ s ɛ d ə n i / kal-SED-ə-nee, or / ˈ k æ l s ə ˌ d oʊ n i / KAL-sə-doh-nee) is a cryptocrystalline form of silica, composed of very fine intergrowths of quartz and moganite. These are both silica minerals, but they differ in that quartz has a trigonal crystal structure, while moganite is monoclinic.Chalcedony's standard chemical structure …

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well as in the chemical composition and IR spectral features, were noted between Mexifire synthetic opals and their natural fire opal counterparts. However ...Citrine is the yellow to brownish-red variety of the mineral Quartz.It is a widely used as a gemstone, and after Amethyst it is the most popular Quartz gem. Most Citrine is formed by heat treating purple Amethyst.Citrine may also be produced by heat-treating Smoky Quartz from certain localities. In some Amethyst deposits, the Amethyst has been partially or …Natural Opal Type 1 – is opal presented in one piece in its natural state apart from cutting or polishing and is of substantially homogenous chemical composition. Natural Opal Type 2 – is opal presented in one piece where the opal is naturally attached to the host rock in which it was formed and the host rock is of a different chemical ...Sep 29, 2023 · Chemical Properties: Composition: Opals are primarily composed of hydrated silicon dioxide (SiO2·nH2O), commonly known as silica. The water content in opals can vary, and it plays a crucial role in the gemstone’s optical properties. Besides that, natural and synthetic opals have the same chemical and structural composition. Appearance and physical properties are also the same. 4 types of synthetic opal. Sellers are required to let people know if they’re getting a synthetic opal, though there are many who prefer a synthetic over the natural thing anyway.Synthetic opals are man-made opals that have the same chemical composition, internal structure, physical properties, and appearance as natural opals. They are often called lab-created opals, lab-grown opals, or cultured opals to indicate their man-made origin. Synthetic opals can exhibit a spectacular play-of-color appearance that often exceeds ...Diamonds: Learn about the properties of diamond, its many uses, and diamond discoveries. Unakite is a pink and green metamorphic rock and a popular gem material. It consists of pistachio-green epidote, pink orthoclase and quartz. It is also used as a construction material, an architectural stone, and a lapidary material.The chemical composition of opals can also affect their durability and stability. Some opals are more prone to cracking or fading over time due to changes in temperature or exposure to light. As a result, opals are often treated or stabilized to improve their appearance and durability. ….

Marble is a metamorphic rock consisting of carbonate minerals that recrystallize under the influence of heat, pressure, and aqueous solutions (most commonly calcite (CaCO 3) or dolomite (CaMg(CO 3) 2) and has a crystalline texture of varying thickness. Marble is typically not foliated (), although there are exceptions.. In geology, the term marble refers …Facts. Mineral: Feldspar. Chemical composition: Orthoclase - KAlSi 3 O 8. Oligoclase and labradorite - solid solution between NaAlSi 3 O 8 and CaAl 2 Si 2 O 8. Color: Yellow, green, red, red-brown, colorless. Refractive …Smith, E. & R. (1999): Black Opal Fossils of Lightning Ridge - Treasures from the Rainbow Billabong, Kangaroo Press, East Roseville. ⓘ Old Coocoran rush (Coocoran A) Smith, E. & R. (1999): Black Opal Fossils of Lightning Ridge - Treasures from the Rainbow Billabong, Kangaroo Press, East Roseville. ⓘ Olga's rushImitation opal is what people usually consider fake opal. It could be made of a material that resembles the appearance of opal but has different chemical and physical properties. They could be either plastic, glass or any other materials…etc. Oparex is certified by GIA as imitation opal. It is a man-made opal which contains 80% resin and 20% ...Besides that, natural and synthetic opals have the same chemical and structural composition. Appearance and physical properties are also the same. 4 types of synthetic opal. Sellers are required to let people know if they’re getting a synthetic opal, though there are many who prefer a synthetic over the natural thing anyway.In simpler terms, an opal is a solid gemstone without a clearly defined shape or form that is solidified from chemical silicon dioxide. There are two types of ...Opal; Chemical composition: SiO 2 +.H 2 O: Crystal system: Amorphous: Hardness: 5- 6 1/2: Refractive index: 1.45 (+.020;-0.080) Specific gravity: 2.15 (+0.07;-0.90) Lustre: …Bloodstone is a dark green variety of chalcedony adorned with a spatter of bright red. It has been a popular gemstone for at least two thousand years and has served as the modern birthstone for the month of March since 1912. Bloodstone is sometimes referred to as "heliotrope" by European authors and in works of the 18th century and earlier.Lab Created Opal Lab Created Aurora Opal Lab Created Bello Opal Lab Created Gilson Opal Lab Created Jelly Opal Lab Created Diamond ... CHEMICAL PROPERTIES. CHEMICAL COMPOSITION: TiO2; DISPERSION: 0.28; REFRACTIVE INDEX: 2.61-2.9; HARDNESS: 6.5; DENSITY: 4.27 g/cm3; Related products. Quartz Rough.Jasper, an aggregate of microgranular quartz and/or cryptocrystalline chalcedony and other mineral phases, is an opaque, impure variety of silica, usually red, yellow, brown or green in color; and rarely blue.The common red color is due to iron(III) inclusions.Jasper breaks with a smooth surface and is used for ornamentation or as a gemstone.It can be highly … Opal chemical composition, Chert is a fine-grained sedimentary rock composed of quartz (SiO2) that is microcrystalline or cryptocrystalline quartz. It is usually organic rock but also occur inorganically as a chemical precipitate or a diagenetic replacement. It occurs as nodules, concretionary masses, and as layered deposits. Name origin: Term is used to refer generally ..., The composition of ooze depends on details of geography: ocean currents, the availability of nutrients in the water, world climate, depth in the ocean, and other factors. ... and plenty of chemical energy being released by crystallization as well as by the breakdown of organic matter in the ooze. ... A less-processed version of opal-CT is what ..., Clastic rocks are composed of fragments, or clasts, of pre-existing minerals and rock. A clast is a fragment of geological detritus, [1] chunks, and smaller grains of rock broken off other rocks by physical weathering. [2] Geologists use the term clastic to refer to sedimentary rocks and particles in sediment transport, whether in suspension or ..., Buy best quality pandora beads synthetic opal for sale online, We have a huge range of pandora beads synthetic opal on sale at very best prices. ... Grown in Lab Chemical Composition: 80% silica & 20% resin Dimensions: 1.2mm to 50mm Grade: AAA Clarity: Opaque Shape: Can do in all., Amber. A heavy, full-bodied, powdery, warm fragrance note, amber oil comes from the Baltic amber tree. "Amber is a warm, powdery, sweet scent. It's a combination of synthetic and natural ingredients such as vanilla, patchouli, labdanum, styrax, and benzoin," says Medina. "Amber provides sophistication and sensuality to a fragrance.", Jones, J.B. and E.R. Segnit (1971), The nature of opal. I Nomenclature and constituent phases. Journal of the Geological Society of Australia: 18: 57-68. , Opal is a mineral species with an amorphous structure. It's composition is silicon dioxide with a variable amount of water. The amount of water (H 2 O) is usually between 2-10% by weight, although contents as high as 20% have been recorded. When opals undergo dehydration as a result of exposure and time they have a tendency to become crazed ..., Synthetic opals created in a lab have the ability to capture the colour-play opal is known for to varying degrees. It is ideal for sourcers and suppliers to meet the demand of retailers and jewellery brands, designers and can easily be cut into cabochons, beads or other shapes.. Cultured opals follow the same play-of-colour and quality of natural opals with the same …, Buy best quality pandora beads synthetic opal for sale online, We have a huge range of pandora beads synthetic opal on sale at very best prices. ... Grown in Lab Chemical Composition: 80% silica & 20% resin Dimensions: 1.25mm to 50mm Grade: AAA Clarity: Opaque Shape: Can do in all $ 37.00 – $ 660.00, Take a look at examples of each of the beautiful birthstone minerals: January Birthstone – Garnet [ Chemical Formula X3Y2(SiO4)3] Spessartine Garnet Crystal (ButtShark) Color: any, but birthstone is …, Removes superficial white and brown imperfections. Provides minimally invasive treatment for fluorosis. Hydrochloric acid aids in chemical stain removal. Silicon carbide microparticles provide gentle mechanical abrasion. Less than 0.2 mm enamel removal. Comes in a direct delivery for an easy and mess-free technique. OpalCups minimize splatter., Garnets (/ ˈ ɡ ɑːr n ɪ t /) are a group of silicate minerals that have been used since the Bronze Age as gemstones and abrasives.. All species of garnets possess similar physical properties and crystal forms, but differ in chemical composition.The different species are pyrope, almandine, spessartine, grossular (varieties of which are hessonite or cinnamon …, Chert (/ ˈ tʃ ɜːr t /) is a hard, fine-grained sedimentary rock composed of microcrystalline or cryptocrystalline quartz, the mineral form of silicon dioxide (SiO 2). Chert is characteristically of biological origin, but may also occur inorganically as a chemical precipitate or a diagenetic replacement, as in petrified wood.. Chert is typically composed of the petrified …, Feb 4, 2017 ... Precious opal from the Tertiary of Ethiopia. (2.3 centimeters across at its widest) A mineral is a naturally-occurring, solid, inorganic, ..., Artificial materials mimicking the opal structure not only give appealing colors but also offer unique optical, mechanical, and other physical properties. In this issue of ACS Central Science, Shen and coauthors draw inspiration from the opal structure to synthesize metal–organic frameworks (MOFs) using a 3D-ordered template replicating a ..., Sedimentary rock - Silica, Clastic, Chemical: Those siliceous rocks composed of an exceptionally high amount of crystalline siliceous material, mainly the mineral quartz (especially microcrystalline quartz and fibrous chalcedony) and amorphous opal, are most commonly known as chert. A wide variety of rock names are applied to cherty rocks reflecting their colour (flint is dark chert; jasper is ..., Iolite (also called Dichroite or Cordierite) is a transparent, violet-blue, light blue, blue, rich blue-violet stone. It is a blue silicate mineral that occurs as crystals or grains in igneous rocks, only as a result of contamination of the magma by aluminous sediment. Its chemical composition is Magnesium Aluminum Silicate (Mg 2 Al 3 O). , Opal is formed from a solution of silicon dioxide and water. As water runs down through the earth, it picks up silica from sandstone, and carries this silica-rich solution into cracks and voids , caused by natural faults or decomposing fossils. As the water evaporates, it leaves behind a silica deposit. This cycle repeats over very long periods ..., Oct 1, 2023 · Chemical Formula SiO2·nH2O; Composition Hydrated Silica; WHERE IS OPAL MINED? Where do Opals come from? Well, Australia has been a world-class source for Opal since the mid-1800s, with considerable mining operations in Lightning Ridge, Coober Pedy, Mintabie, Andamooka and others too. , Opal · it's made from essentially amorphous or non-crystalline material · despite the lack of crystal structure, opal does display internal order! · composition = ..., Classified within the oxides with formula SiO2nH2O. The composition is the same as quartz with the difference that the opal is hydrated, that is, it has water molecules in its composition. Opal stones are a precious stone that is currently used in jewelry and also for decorative purposes. The popularity of this gem was wide for a considerable ..., The chemical composition which was given by Tschermak in 1884 for this dravite approximately corresponds to the formula NaMg 3 (Al,Mg) 6 B 3 Si 6 O 27 (OH), which is in good agreement (except for the OH content) with the endmember formula of dravite as known today. Dravite varieties include the deep green chromium dravite and the vanadium dravite., Opal definition, a mineral, an amorphous form of silica, SiO2 with some water of hydration, found in many varieties and colors, including a form that is milky white. See more., Opal is a mineraloid because it is amorphous hydrated silica. Despite its mineral-like properties, opal’s chemical structure is hydrated with varied water concentration. Because of this variance, the stone’s structure isn’t fixed or organized and thus, qualifies as a mineraloid., Hindustan Composites News: This is the News-site for the company Hindustan Composites on Markets Insider Indices Commodities Currencies Stocks, RARE Mint Seafoam Genuine Opal Necklace,14K Gold Filled Opal Gemstone Necklace,Large Opal Pendant,Rainbow,October Birthstone,Lab Created hangingbyathread1 . ... These opals are made with the exact same chemical composition as a natural, mined from the Earth opal would have., Pink opal is found in Peru and Mexico. It is translucent to opaque and comes in brownish pink to pure pink. Pink opal is a combination of opal grains in chalcedony and cristobalite. The chalcedony makes the material slightly more durable and it typically has a Mohs hardness of 5-5.5 but can be up to 6. , An image of an opal grain showing conchoidal fracture was imaged at low magnification (S-101). An opal grain was also imaged with backscatter electrons (BEI mode) to examine sample composition (S-102), with an accelerating voltage of 23 kV and pressure of 28 Pa. Opal shards are devoid of crystalline structure and cleavage. , Obsidian is an igneous rock that forms when molten rock material cools so rapidly that atoms are unable to arrange themselves into a crystalline structure. It is an amorphous material known as a " mineraloid ." The result is a volcanic glass with a smooth uniform texture that breaks with a conchoidal fracture (see photo)., Fire Opal is rare compared to other colors because of its chemical structure and depositional environment. To illustrate, opal stones reflect a red color when white light refracts upon sections of larger silica spheres. And the composition of larger silica spheres in an opal stone is due to a less common depositional environment., Composite natural opal consists of natural opal laminates, manually cemented or attached to another material. The opal component is natural opal. There are ..., Earlier work by some of us2 supported these conclusions, and a comprehensive re-examination of natural opals has confirmed that the structure can vary from almost perfect α-cristobalite to ... , Sedimentary rock - Silica, Clastic, Chemical: Those siliceous rocks composed of an exceptionally high amount of crystalline siliceous material, mainly the mineral quartz (especially microcrystalline quartz and fibrous chalcedony) and amorphous opal, are most commonly known as chert. A wide variety of rock names are applied to cherty rocks reflecting their colour (flint is dark chert; jasper is ...