Search results
Results from the WOW.Com Content Network
Gemstones of the World revised 5th edition, 2013 by Walter Schumann ISBN 978-1454909538 Smithsonian Handbook: Gemstones by Cally Hall, 2nd ed. 2002 ISBN 978-0789489852 v
In 1986, California named benitoite as its state gemstone, a form of the mineral barium titanium silicate that is unique to the Golden State and only found in gem quality in San Benito County. [ 80 ] ^ Colorado is the only state whose geological symbols reflect the national flag's colors: red (rhodochrosite), white (yule marble), and blue ...
Jewelry applications of precious opal can be somewhat limited by opal's sensitivity to heat due primarily to its relatively high water content and predisposition to scratching. [11] Combined with modern techniques of polishing, a doublet opal can produce a similar effect to Natural black or boulder opal at a fraction of the price.
The Star of Bombay is a 182- carat (36.4-g) cabochon -cut star sapphire originating in Sri Lanka. The violet-blue gem was given to silent film actress Mary Pickford by her husband, Douglas Fairbanks. She bequeathed it to the Smithsonian Institution.
Cut (gems) A decorative glass crystal about 4 cm (1.6 in) in diameter, having a facet cut often applied for gemstones. At some positions, coloured light (see rainbow colouring) can be regarded caused by the intended optical prism effect of the cut. A gemstone desired to be used in jewelry is cut depending on the size and shape of the rough ...
New York City. , New York. , United States. Website. www .gemscience .net. Gemological Science International, or GSI, is an independent gemological organization that is one of the largest gemological entities in the world, with offices in four continents. [1] [2] [3]
Logan Sapphire. Star of Bombay, given to Mary Pickford by Douglas Fairbanks, Sr. Star of India. Stuart Sapphire. Black Star of Queensland. Star of Adam, with a weight of 1,404.49 carats (280.898 g), it is the largest star sapphire in the world. Queen Marie of Romania Sapphire.
Diamond[ a] is a gemstone formed by cutting a raw diamond. Diamonds are one of the best-known and most sought-after gems, and they have been used as decorative items since ancient times. The hardness of diamond and its high dispersion of light —giving the diamond its characteristic "fire"—make it useful for industrial applications and ...