Opalescence or play of color is the optical phenomenon displayed by the mineraloidgemstoneopal,[1] a hydratedsilicon dioxide.[2] However, each of the three notable types of opal – precious, common, and fire[3] – display different optical effects; therefore, the intended meaning varies depending on context.
The general definition of opalescence is a milky iridescence displayed by an opal, which describes the visual effect of precious opal very well, and opalescence is commonly used in lay terms as a synonym for iridescence.[4]
In contrast, common opal does not display an iridescence, but often exhibits a hazy sheen of light from within the stone – the phenomenon that gemologists strictly term as opalescence.[5] This milky sheen displayed by opal is a form of adularescence.[6]
Fire opal is a relatively transparent gemstone with a vivid yellow-orange-red color and rarely displays iridescence.[2]
Rough sample of common opalRough sample of precious opal, showing iridescence
The optical effects seen in various types of opal are a result of refraction (precious and fire) or reflection (common) due to the layering, spacing, and size of the myriad microscopic silicon dioxide spheres and included water (or air) in its physical structure.[2][3] When the size and spacing of the silica spheres are relatively small, refracted blue-green colors are prevalent; when relatively larger, refracted yellow-orange-red colors are seen; and when larger yet, reflection yields a milky-hazy sheen.[2][6]
Tyndall effect in opalescent glass: it appears blue from the side, but orange light shines through.[7]
In a physical sense, some cases of opalescence could be related to a type of dichroism seen in highly dispersed systems with little opacity. Due to Rayleigh scattering, a transparent material appears yellowish-red in transmitted white light and blue in the scattered light perpendicular to the transmitted light.[7] The phenomenon illustrated in the bottom photo is an example of the Tyndall effect.
opalescence, opalescent, redirects, here, album, hopkins, opalescent, album, this, article, about, gemstone, rarity, persian, with, like, long, bushy, tail, list, little, pony, friendship, magic, characters, play, color, optical, phenomenon, displayed, mineral. Opalescent redirects here For the album by Jon Hopkins see Opalescent album This article is about the gemstone For Rarity s persian cat with a fox like long bushy tail see List of My Little Pony Friendship is Magic characters Opalescence or play of color is the optical phenomenon displayed by the mineraloid gemstone opal 1 a hydrated silicon dioxide 2 However each of the three notable types of opal precious common and fire 3 display different optical effects therefore the intended meaning varies depending on context The general definition of opalescence is a milky iridescence displayed by an opal which describes the visual effect of precious opal very well and opalescence is commonly used in lay terms as a synonym for iridescence 4 In contrast common opal does not display an iridescence but often exhibits a hazy sheen of light from within the stone the phenomenon that gemologists strictly term as opalescence 5 This milky sheen displayed by opal is a form of adularescence 6 Fire opal is a relatively transparent gemstone with a vivid yellow orange red color and rarely displays iridescence 2 Rough sample of common opalRough sample of precious opal showing iridescence The optical effects seen in various types of opal are a result of refraction precious and fire or reflection common due to the layering spacing and size of the myriad microscopic silicon dioxide spheres and included water or air in its physical structure 2 3 When the size and spacing of the silica spheres are relatively small refracted blue green colors are prevalent when relatively larger refracted yellow orange red colors are seen and when larger yet reflection yields a milky hazy sheen 2 6 Tyndall effect in opalescent glass it appears blue from the side but orange light shines through 7 In a physical sense some cases of opalescence could be related to a type of dichroism seen in highly dispersed systems with little opacity Due to Rayleigh scattering a transparent material appears yellowish red in transmitted white light and blue in the scattered light perpendicular to the transmitted light 7 The phenomenon illustrated in the bottom photo is an example of the Tyndall effect See also editAventurescence Labradorescence Moonstone gemstone References edit opalescent 2019 In Noah Webster s 1828 American Dictionary of the English Language Retrieved January 7 2019 from https 1828 mshaffer com d word opalescent a b c d Opal Gemstone Information Gemstone Select 2018 Retrieved 2019 01 08 a b Douma M curator 2008 Opal In Cause of Color Retrieved January 8 2019 from https webexhibits org causesofcolor 15F html opalescent Merriam Webster com Dictionary Retrieved 2019 01 08 Opal Description Gemological Institute of America 2019 Retrieved 2019 01 08 a b Smigel Barbara W 2012 Optical Phenomena in Gemstones In Introduction to Gemology Retrieved January 8 2019 from http www bwsmigel info Lesson6 DE Optical Phenomena html a b Douma M curator 2008 Blue and Red In Cause of Color Retrieved 2005 from http www webexhibits org causesofcolor 14B html Retrieved from https en wikipedia org w index php title Opalescence amp oldid 1156309701, wikipedia, wiki, book, books, library,
