Why do so many different fouresent minerals emit different colors when illuminated with ultraviolet light?
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Since the UV light has particular wavelength and energy, the atoms in the florescent material absorbs that energy and goes to excited state from ground state. but it nomore stable in the excited state. so it emits an energy with is in the range of visible region with some particular wavelength and returns to ground state. the wavelength corresponding colour is visible to us....
965507
Visible light is actually made up of different colors. Each color bends by a different amount when refracted by glass or other substances. When light passes through a lens or prism shorter wavelengths, like purple and blue light, bend the most. Longer wavelengths, like red and orange light, bend the least. That's why visible light can be split, or dispersed, into different colors.
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Emission lines of different wavelength depending upon what is being studied.
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You would have to look at the color banding. How many color bands does it contain? What colors are in the banding?\n\nMost gneiss are igneous in origin; the protolith being either granite or diorite.\n\nGranite usually has some Kspar which tends to be pink. So granitic gneiss would have some white, pink, & dark banding.\n\nDiorite which is also igneous is black & white which will produce a gneiss w/ black & white banding.\n\nGneiss can form from other types of rocks such as schist which is the metamorphic form of phyllite which is the metamorphic form of slate which is the metamorphic form of the sedimentary rock shale.\n\nShale forms from clays which usually contain high amounts of aluminum. As it goes through different stages of metamorphism it tends to have a sheen this is due to the mineral mica.\n\nIf it tends to have a sheen along w/ the banding then it contains an abundance of mica & probably means that it came from the mudstone/slate or one of its metamorphic forms.
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it's reactive to light
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It is not due to the chemistry of copper or gold.\n\nIt is due to the electronic band structure. The two metals unusually have a band structure that causes them to absorb light at certain frequencies rather than reflecting it.
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The chemical composition of diferent minerals is what makes them different colors.  This is why jade is green, sapphires (my birthstone) are blue, rubies are red, etc.   This is also whay there are color variations within different types of the same mineral (yellow diamonds, colorless diamonds, etc.)
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Pure quartz is clear and translucent, but natural quartz is typically tainted with impurities, and it takes on the color of those. Here are some examples:\n\n# Amethyst's color is due to an iron (ferric, Fe+3) impurity-induced color center\n# Citrine's color is due to an iron (ferrous, Fe+2) impurity-induced color center\n# Milky quartz's color is due to microscopic air, carbon dioxide, or water inclusions\n# Rose quartz's (crystalline) color is due to aluminum and phosphorus impurities - massive rose quartz's color is due to microscopic and, as yet, unidentified dumortierite-like fibers\n# Smoky quartz's color is due to an aluminum impurity-induced color center aided by natural irradiation
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1. Color. This can vary based on the amount or type of impurities in the mineral, or because of different ratios of certain elements such as (Mg,Fe)[X]Si[8]O[22](OH)[2] in amphiboles - the X and the ratio of Mg to Fe can vary.\n\n2. Index of Refraction. This is the change in angle of light passing through the mineral, and can be changed by anion content just like the color.\n\n3. Crystal shape. This can actually be completely different in an alteration mineral than the pure crystallized form. i.e. mineral formed from alteration of pyroxene can retain the crystal (hexagonal) form which may be completely different than the shape it would have if it crystallized out of solution or in a magma chamber.
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No.  The opposite (emitting visible light after absorbing UV) is possible.  When light is emitted, it must have the same energy as the light absorbed, or it must have a lower energy.  UV light has higher energy than visible light, and so a material can't absorb visible and emit UV.
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Web_Maven got it right but only if you already know the right answer. Here is how it goes.\n \nThe first part you got, when you mix lights of color red, green and blue you can get other colors and white. But why doesn't this work with pigments? Because pigments do not emit light, what they do, is absorb all the other colors except the one(s) you see. If you throw white light on a red pigment, it will absorb all colors except red. If you mix the three pigments, the mix absorbs all colors.
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Are you talking about rocks that glow in the dark?\nHere are some pictures of rocks that glow in the dark...\n\nhttp://www.worldofrockhounds.com/hackmanite.html  \nhttp://www.scienceattractions.com/minerals.htm  \nhttp://www.worldofrockhounds.com/calcite.html\n\nHere is a list of flourescent rocks. Try looking for them on the Internet.\nScheelite (fluorescent blue) \nHardystonite (fluorescent purple) \nAnglesite and cerussite (fluorescent orange) \nHalite (fluorescent red) \nSapphire (blue and red fluorescence) \nZircon (orange fluorescence) \nAdamite (lemon-yellow)
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When salts of different metals are burned, they produce different colors. So, fireworks use metals to produce different colors.
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they make colors usually white stand out more. if you have glow in the dark stuff it will make that stand out too
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That's light in the visible spectrum. I'd imagine a great deal of compounds could, especially since "great absorbance" means nothing, in scientific terms.
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It's all about the color spectrum- ROYGBIV- And think more Blue, Indigo, Violet , more insects. More red, orange- less insects.\n\nMost insects see better in UV and are thus generally attracted to \nshort wave lengths toward that end of the spectrum. Insects do not see in the red end of the spectrum.
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A variety of impurities and structural imperfections cause different colors in diamonds, including yellow, pink, blue, red, green, brown, and other hues.