Morganite
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Morganite is a pink colored gem quality beryl, orange/yellow morganite is sometimes also found, it turns pink upon high temperature treatment. Color banding is common in morganite.
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[edit] J. P. Morgan
By the turn of the century, J. P. Morgan (the famous financier) had become one of the most important collectors of gems and minerals and had assembled the most important gem collection in the USA as well as of American gemstones (over 1000 pieces). Tiffany & Co. actually assembled his first collection -- which basically implied that their "chief gemologist" George Frederick Kunz built the collection for JP Morgan -- which was exhibited at the World's Fair in Paris in 1889. The exhibit won two golden awards and drew the attention of important scholars, lapidaries and the general public. [1]
George Frederick Kunz then continued to build a second, even finer, collection which was exhibited in Paris in 1900. Collections have been donated to the American Museum of Natural History in New York where they were known as the Morgan-Tiffany and the Morgan-Bement collections. [2]
[edit] The discovery
Morganite was first discovered together with other gemstone minerals such as Tourmaline and Kunzite in California in the early twentieth century at Pala. This started a bonanza for these quite popular gemstones which drew the attention of George Frederick Kunz, knowing Pink Beryl was quite a rarity. [3]
It was George Frederick Kunz who suggested to name the pink variety of Beryl after his biggest customer JP Morgan in 1911: Morganite. [4]. Ever since, the stone has held a certain popularity with Tiffany's though it still remains a relatively scarce gem.
[edit] Chemical and physical properties
The chemical formula of morganite is: Be3Al2(SiO3)6 beryllium-aluminium silicate.
The chemical composition of beryl is beryllium (14%) aluminium (19%) silicate (67%), usually containing alkali ions, other minerals, water, and gases. It crystallizes in hexagonal shapes, known as habit, and is in the dihexagonal-dipyramidal class of the Hexagonal crystal system. Beryls sometimes crystalize in well formed hexagonal prisms with pedion (flat) terminations. It has refractive index values of 1.57 to 1.58 with weak dichroism. Cleavage is absent to poor in one direction. The hardness is 7.5-8 on the Mohs hardness scale, and the specific gravity ranges from 2.66-2.83.[5]
Many sources attribute morganite's color to the element manganese in interstitial sites in the beryl's ring structure[6]. Other references attribute the color to the element cesium[7]
[edit] Different types of Beryl
Colorless - goshenite, Green - emerald, Blue & blue/green - aquamarine, Pink - morganite, Yellow - heliodor, Red - bixbite
Morganite may also be known as pink beryl, or in the jewelry trade as pink emerald. Attempts to change the names of beryl gem varieties are a matter of some contention in the gem trade.
[edit] Value as a gemstone
Morganite is generally considered to be about as common as the other beryls, aquamarine and heliodor. Its value is influenced by demand, and is generally less well known than aquamarine, tending to depress its value. The only beryl which is considered to be rare, other than emerald, is the Red Beryl, bixbite which is primarily found in the Wah-Wah Mountains of Utah.
[edit] Enhancements
Morganite should be considered to be routinely heat treated to remove patches of yellow.
[edit] References
- ^ Morgan and his gem collection, In George Frederick Kunz: Gems and Precious Stones of North America, New York, 1890, accessed online February 20, 2007
- ^ Morgan and his gem collections, donation to AMNH, In George Frederick Kunz: History of Gems Found in North Carolina, Raleigh, 1907, accessed online February 20, 2007
- ^ Morganite discovery in Pala, CA, AGTA website, accessed online February 20, 2007
- ^ Morganite, International Colored Gemstone Association, accessed online January 22, 2007
- ^ Weinstein, Michael, 1958, The World of Jewel Stones, p. 104 - 107, Sheridan House, New York
- ^ [1], article, New Mexico Facetor's Guild, accessed online March 19, 2007
- ^ Hurlbut, Cornelius S. Jr, & Kammerling, Robert C., 1991, Gemology, p. 203, John Wiley & Sons, New York
