افتح القائمة الرئيسية

ياقوت

الياقوت حجر كريم يتراح لونه من الوردي إلى الأحمر، وهو أحد أصناف المعدن كورندم (اكسيد الألومنيوم). اللون الأحمر الشائع سببه عنصر الكروم.

Ruby
Corundum-winza-17d.jpg
Natural ruby crystals from Winza, Tanzania
العامة
التصنيفOxide mineral variety
الصيغة
(repeating unit)
aluminium oxide with chromium, Al2O3:Cr
النظام البلوريTrigonal
Crystal classHexagonal scalenohedral (3m)
H-M symbol: (3 2/m)
Space groupR3c[1]
التعرف
ColorNear colorless through pink through all shades of red to a deep crimson
Crystal habitTerminated tabular hexagonal prisms
CleavageNo true cleavage
FractureConchoidal, splintery
TenacityBrittle
Mohs scale hardness9.0
LusterSubadamantine, vitreous, pearly (on partings)
StreakWhite
DiaphaneityTransparent, translucent
الجاذبية النوعية3.97 – 4.05
الصفات البصريةUniaxial -
Refractive indexnω=1.768–1.772
nε=1.760–1.763
Birefringence0.008
PleochroismStrong: purplish-red – orangy-red
التشتت0.018
Ultraviolet fluorescenceRed under longwave
References[2]

وقد استخدمت بلورة ياقوت مصنَعة لإنتاج أول ليزر.

كورندم هو الياقوت عندما يشوبه كروم

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فهرست

الخصائص الطبيعية

 
Crystal structure of rubies

Rubies have a hardness of 9.0 on the Mohs scale of mineral hardness. Among the natural gems only moissanite and diamond are harder, with diamond having a Mohs hardness of 10.0 and moissanite falling somewhere in between corundum (ruby) and diamond in hardness. Sapphire, ruby, and pure corundum are α-alumina, the most stable form of Al2O3, in which 3 electrons leave each aluminum ion to join the regular octahedral group of six nearby O2− ions; in pure corundum this leaves all of the aluminum ions with a very stable configuration of no unpaired electrons or unfilled energy levels, and the crystal is perfectly colorless.

 
Transmittance of ruby in optical and near-IR spectra. Note the two broad violet and yellow-green absorption bands and one narrow absorption band at the wavelength of 694 nm, which is the wavelength of the ruby laser.


الياقوت مقابل الزفير الوردي

Generally, gemstone-quality corundum in all shades of red, including pink, are called rubies.[3][4] However, in the United States, a minimum color saturation must be met to be called a ruby; otherwise, the stone will be called a pink sapphire.[3] Drawing a distinction between rubies and pink sapphires is relatively new, having arisen sometime in the 20th century. Often, the distinction between ruby and pink sapphire is not clear and can be debated.[5] As a result of the difficulty and subjectiveness of such distinctions, trade organizations such as the International Colored Gemstone Association (ICGA) have adopted the broader definition for ruby which encompasses its lighter shades, including pink.[6][7]

التواجد الطبيعي

The Mogok Valley in Upper Myanmar (Burma) was for centuries the world's main source for rubies. That region has produced some exceptional rubies, however in recent years few good rubies have been found. In central Myanmar, the area of Mong Hsu began producing rubies during the 1990s and rapidly became the world's main ruby mining area. The most recently found ruby deposit in Myanmar is in Namya (Namyazeik) located in the northern state of Kachin.

العوامل المؤثرة على القيمة

Rubies, as with other gemstones, are graded using criteria known as the four Cs, namely color, cut, clarity and carat weight. Rubies are also evaluated on the basis of their geographic origin.



الياقوت الإصطناعي والمقلـَّد

Artificial ruby under a normal light (top) and under a green laser light (bottom). Red light is emitted

أرقام قياسية وياقوتات شهيرة

  • The Sunrise Ruby is the world's most expensive ruby, most expensive coloured gemstone, and most expensive gemstone other than a diamond. In May 2015, it sold at auction in Switzerland to an anonymous buyer for US$30 million.[8]
  • A synthetic ruby crystal became the gain medium in the world's first optical laser, conceived, designed and constructed by Theodore H. "Ted" Maiman, on the 16th of May, 1961 at Hughes Research Laboratories.[9][10] The concept of electromagnetic radiation amplification through the mechanism of stimulated emission had already been successfully demonstrated in the laboratory by way of the Maser, using other materials such as ammonia and, later, ruby, but the Ruby Laser was the first device to work at optical (694.3 nm) wavelengths. Maiman's prototype laser is still in working order.


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الاشارات التاريخية والثقافية

  • In Job 28:18 31 and Proverbs 3:15 31, wisdom is more valuable than rubies. In Proverbs 31:10 31, a wife of noble character is worth more than rubies.
  • An early recorded transport and trading of rubies arises in the literature on the North Silk Road of China, wherein about 200 BC rubies were carried along this ancient trackway moving westward from China.[11]
  • Rubies have always been held in high esteem in Asian countries. They were used to ornament armor, scabbards, and harnesses of noblemen in India and China. Rubies were laid beneath the foundation of buildings to secure good fortune to the structure.[12]

انظر أيضاً

الهامش

  1. ^ Corundum data on Webmineral Archived October 1, 2007, at the Wayback Machine.
  2. ^ Ruby on Gemdat.org Archived March 17, 2015, at the Wayback Machine.
  3. ^ أ ب Matlins, Antoinette Leonard (2010). Colored Gemstones. Gemstone Press. p. 203. ISBN 0-943763-72-X. Archived from the original on May 2, 2016. Cite uses deprecated parameter |deadurl= (help)
  4. ^ Reed, Peter (1991). Gemmology. Butterworth-Heinemann. p. 337. ISBN 0-7506-6449-5. Archived from the original on January 2, 2017. Cite uses deprecated parameter |deadurl= (help)
  5. ^ Wise, Richard G. "Gemstone Connoisseurship; The Finer Points, Part II". Archived from the original on April 26, 2012. Cite uses deprecated parameter |deadurl= (help)
  6. ^ Hughes, Richard W. "Walking the line in ruby & sapphire". ruby-sapphire.com. Archived from the original on January 13, 2012. Cite uses deprecated parameter |deadurl= (help)
  7. ^ Federman, David. "Pink Sapphire". Modern Jeweler. Archived from the original on January 31, 2012. Cite uses deprecated parameter |deadurl= (help)
  8. ^ "World's most expensive coloured gem sells for $30m". BBC. May 13, 2015. Archived from the original on May 13, 2015. Retrieved May 13, 2015. Cite uses deprecated parameter |deadurl= (help)
  9. ^ خطأ استشهاد: وسم <ref> غير صحيح؛ لا نص تم توفيره للمراجع المسماة maiman
  10. ^ "Laser inventor Maiman dies; tribute to be held on anniversary of first laser". Laser Focus World. May 9, 2007. Archived from the original on September 27, 2007. Retrieved May 14, 2007. Cite uses deprecated parameter |deadurl= (help)
  11. ^ C. Michael Hogan, Silk Road, North China Archived October 2, 2013, at the Wayback Machine., The Megalithic Portal. 19 November 2007
  12. ^ Smith, Henry G. (1896). "Chapter 2, Sapphires, Rubies". Gems and Precious Stones. Charles Potter Government Printer, Australia. Archived from the original on September 29, 2007. Cite uses deprecated parameter |deadurl= (help)

وصلات خارجية