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  2. Chemical impurity - Wikipedia

    en.wikipedia.org/wiki/Chemical_impurity

    These gems have slight impurities that act as chromophores and give the stone its color. An example is the gem family beryl which has the base chemical formula of Be 3 Al 2 (SiO 3 ) 6 . Pure beryl will appear colorless but this rarely occurs and the presence of trace elements change its color.

  3. Sapphire - Wikipedia

    en.wikipedia.org/wiki/Sapphire

    Chemical dopants can be added to create artificial versions of the ruby, and all the other natural colors of sapphire, and in addition, other colors never seen in geological samples. Artificial sapphire material is identical to natural sapphire, except it can be made without the flaws that are found in natural stones.

  4. List of purification methods in chemistry - Wikipedia

    en.wikipedia.org/wiki/List_of_purification...

    Water purification combines a number of methods to produce potable or drinking water. Downstream processing refers to purification of chemicals, pharmaceuticals and food ingredients produced by fermentation or synthesized by plant and animal tissues, for example antibiotics, citric acid, vitamin E, and insulin.

  5. Flux (metallurgy) - Wikipedia

    en.wikipedia.org/wiki/Flux_(metallurgy)

    In the process of smelting, inorganic chlorides, fluorides (see fluorite), limestone and other materials are designated as "fluxes" when added to the contents of a smelting furnace or a cupola for the purpose of purging the metal of chemical impurities such as phosphorus, and of rendering slag more liquid at the smelting temperature.

  6. Beryl - Wikipedia

    en.wikipedia.org/wiki/Beryl

    The word beryl – Middle English: beril – is borrowed, via Old French: beryl and Latin: beryllus, from Ancient Greek βήρυλλος bḗryllos, which referred to a 'precious blue-green color-of-sea-water stone'; [2] from Prakrit veruḷiya, veḷuriya 'beryl' [8] [a] which is ultimately of Dravidian origin, maybe from the name of Belur or ...

  7. Quartz - Wikipedia

    en.wikipedia.org/wiki/Quartz

    [22] [27] However, there is a significant change in volume during this transition, [28] and this can result in significant microfracturing in ceramics during firing, [29] in ornamental stone after a fire [30] and in rocks of the Earth's crust exposed to high temperatures, [31] thereby damaging materials containing quartz and degrading their ...

  8. Chemical compound found in U.S. drinking water that could ...

    www.aol.com/chemical-compound-found-u-drinking...

    A group of international researchers has discovered a previously unknown chemical compound in U.S. drinking water — and it could be toxic.. The compound — known as chloronitramide anion — is ...

  9. Gemology - Wikipedia

    en.wikipedia.org/wiki/Gemology

    Specific gravity, also known as relative density, varies depending upon the chemical composition and crystal structure type. Heavy liquids with a known specific gravity are used to test loose gemstones. Specific gravity is measured by comparing the weight of the gem in air with the weight of the gem suspended in water.