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Print › EOSC 118 Module B | Quizlet EOSC 118 Module B Study online at quizlet.com/_6tnx9 1. 'Maxixe-type' beryl found only in Brazil, dark 17. Common Almost all (~99%) sapphires and rubies velvety blue but color fades treatments for are heat treated to change colours, in light Corundum intensify them, and increase clarity. 2. "Big Three Gemstones" Emeralds, Rubies, 18. Crest: Highest wave point Sapphires 19. Definition of Minerals that display different colors 3. "Replacements" of elements at the farthest distance Pleochorism depending on crystallographic direction in gemstone minerals from the larger magma of the stone being viewed predominantly occur within body (or cooled intrusion) 20. Diamond Testers Test electrical conductivity which zone of a pegmatite that the pegmatite field? emanates from 21. Dichroscope determining optic class a mineral or gem belongs to 4. 3 sources of light 1. Natural: noon sunlight, well balanced 22. Electromagnetic Continuous, high is gamma rays, low is 2. Incandescent Lamps: Spectrum radio waves skewed towards warm red 23. Emerald (Kind of Vibrant green variety of beryl, most 3. fluorescent lamps: 'cool Beryl) valuable. Columbia white', output blue and green 24. Frequency Number of waves passing a point 5. Allochromatic 'other-colored' from 25. How is Beryl Hexagonal, harder than quartz, basal impurity. ie Emerald distinguishable? cleavage, can be pleochloric 6. Amplitude Vertical distance b/w 26. How is corundum mineral and fluid inclusions, low crest/trough and equil line distinguishable? dispersion, high density, and two refractive indices (it is dichroic). 7. Aquamarine (Kind of Beryl) Light to dark blue, most Hexagonal nature, hardness of 9. coveted is deep blue. Larger clearer crystals than 27. How is topaz Rough: crystal shape, hardness 8 emeralds. recognized and distinguished 8. Are some Emeralds more Yes from other rare than diamonds? materials? 9. Blue corundum Sapphire 28. Idiochromatic 'self-colored', inherent from crystal 10. Burmese sapphires Highly valued for their structure. ie. Turquoise saturated blue 29. If Violet is Yellow (color we see if complimentary to 11. Characteristics of Beryl Colorful, hard, resistant to absorbed, what colors that are absorbed) acids, form large crystals, are the hexagonal prisms wavelengths seen and produced in 12. Chelsea Filter Aka Emerald Filter, color our eyes? filter, only allows red and green to pass through 30. is Visible light is a yes form of 13. Chromophore Element responsible for electromagnetic coloration of mineral ie. Cr radiation? in Emerald which gives it green hue 31. Isotropic media That it only has 1 refractive index means? 14. Color and geo environment: colorless Beryl pegmatite 32. Light travels as a wavelength and frequency change wave, with together, because they are different ways 15. Color, deviations and geo Light-dark blue wavelength and to measure the same property environment: Aquamarine Fe, Al, Na frequency related Pegmatite to that because 16. Color, deviations and geo Green 33. Loupe Hand lens, handheld magnifier.Most environment: Emerald Cr, V, Al are made as 'triplets' to minimize Metasomatic zones distortion of transmitted image. After eye, it is next most important tool for collecting visual information 34. Morganite Pink variety of beryl 54. What are the 3 main Depth of emplacement below the geochemical family surface 35. Pleochloric 2 different colors factors? Range of temperature 36. Pseudochromatic 'false-colored' from phyiscal Type of rare element enrichment optics. 55. What are the 4 Abyssal (high temp, variable 37. Quartz Gems Hardness 7 geochemical family Pressure) groups? Muscovite (low T, high P) 38. Red Corundum Ruby Rare-element (low T, low P), produce 39. Refractometer Determines refractive index of most gemstones faceted stone through Miarolitic (med T, low P) refraction and reflection of 56. What colors can Kunzite (Pink), Hiddenite (green), light Spodumene have North Carolina and Kabul 40. Rubies with Pigeon's Pure red with a hint of blue, Afghanistan, Light yellow Blood red colouration are highly valued. Originate 57. What colors can Colorless:Pure from Burma topaz have? Common: light brown, yellow 41. Sapphires from Kashmir Velvety-Blue 58. What does 'Gota de Finest quality of beryl, meaniging 42. spectral emittance curve 'more red' Aceite' mean? 'drop of oil' in spanish shows that tungsten light 59. What helps fluxing agents bulbs emits light that pegmatites grow is______ than noon bigger crystals? sunlight 60. What is a common tabular 43. Spectroscope differentiate specific stones shape for euhedral from one another Absorption spodumene crystals? of light transmitted through gemstone 61. What is a longer Red wavelength? (color) 44. Sri Lanka Sapphires Cornflower blues, not to mention their very large sizes, 62. What is a short Violet are also prized wavelength? (color) 63. What is Beryls 7.5 to 8 45. Topaz and Spodumene Pegmatite are what kind of gems? hardness on the Mohs scale? 46. Trough Lowest wave point 64. What is corundum's Al2O3 47. Type I Gem Free of inclusions, all Beryl basic structure? EXCEPT Emerald 65. What is Dispersion? when white light enters or leaves a 48. Type III Gem Emerald material at angles other than 90 degrees 49. Visible Spectrum called 'white light' ROY G BIV 66. What is Pegmatite Granite it key factor. Undergo Genesis? fractionation, sequential 50. Wavelength Distance b/w 2 successive crests/troughs crystallization of minerals as granitic magma cools 51. What are Organic Gems? Pearls, Amber, Coral 67. What is Spodumene Colorless to light pink, Hardness: 52. What are Pegmatites? Intrusive igneous rocks that and What are its 6.5-7 are texturally very coarse to basic Qualities? gigantic in size. Similar to 68. What is the color Neon blue variety of Tourmaline. granite, but enriched with rare Paraiba? Rarest elements 69. What is the 7 53. What are the 2 common (1) Oiling: Emeralds, improves hardness of treatments for Beryl? clarity and adds durability amethyst? (2) Heat Treated: For mediocre color, of green and yellow. 70. What is the 9, one of the most durable Brings out BLUE Hardness of commercial stones Corundum? 71. What is the key to corundum's color (Al) in this simple formula is the key to generating the striking colours of corundum's variety? gem varieties. 72. What is the most precious Quartz Gem? Opal 73. What is Tourmaline? Kind of pegmatite. Hardness of 7. Opaque black is most common 74. When is there the finest color of Beryl? When some elements do not substitute into crystal structure 75. Where does Tourmaline come from? Brazil, Madagascar, Afghanistan, USA 76. Which common mineral grouping does pyroxene spodumene belong to? 77. Which gem changes colour when viewed alexandrite under different forms of lighting? 78. Why are Aquamarines less rare than B/C chromophore, Iron, is more common Emeralds? 79. Why is pegmatite genesis rare? Require geological environment with lots of granitic rocks. Pegmatites need to be in tectonic environment allowing them to be brought upwards into the crust Slow and steady erosion is required 80. Why is there a variety of color for Beryl? Almost all contain minor substitutions in octahedral sites (normally in Al) 81. Why is Tourmaline's mineral called So many different elements enter into the structure 'garbage bag'?.
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