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Roger Weller, geology instructor

wellerr@cochise.edu

Moonstones
by Dannielle Farmer
Physical Geology
Spring 2012
                  

From the Moon to the Earth

     The first thing you should know about the moonstone is that this gemstone is in fact from Earth. The moonstone belongs to the large mineral group feldspar, which is not uncommon. Almost two-thirds of all rocks on Earth consist of this group. This gemstone comes from a variety of feldspar known as “adularia”, which can be found in the European Alps near the Adula Group. This is a potassium aluminosilicate of gemstone quality, and so many experts refer to it as “adularescence”. Another name that moonstone is also mentioned as is “selenite”; this come from the Greek word “selene” which means moon.

 

Description: http://skywalker.cochise.edu/wellerr/mingem/gemtl/moonstone/6moonstone-carving-vista3503.jpg

Photo courtesy of Roger Weller/Cochise College

 Finding Moonstones

     The traditional moonstones, the ones that are nearly transparent and with a bluish shimmer, come from Sri Lanka. However, Sri Lanka is not the only place that you can find moonstones; they are also found in the United States, Brazil, Australia, Myanmar, and Madagascar.  

     In Sri Lanka there are very few places where moonstones are found in high concentration. One of those places is Meetiyagoda, many inhabitants of that area believe that because of the high concentration of moonstone in that area that it has been blessed by the moon. At the mines in Meetiyagoda you can see deep down into the hole, or ever go down into the bottomless shafts where these stones are found. However, more recently, the mines in Sri Lanka have run out of the more wanted and enchanting moonstone. The valued blue moonstone seems to have vanished from the mines in Meetiyagoda; all that is left is a more transparent stone with a milky color mixed into it.

 

Description: Moonstone

http://www.modernjeweler.com/web/online/Colored-Gemstone-Gem-Profiles/Moonstone/1$522 

     In the United States, the moonstone is the state gem of Florida. Ironically, the moonstone is not found in Florida. However, in the United States, moonstone can be found in Alabama, California, Connecticut, Georgia, Indiana, Nebraska, New Mexico, North Carolina, Rhode Island, Tennessee, and Virginia.

 

Description: http://www.flheritage.com/images/facts/symbols/moonstone.jpg

http://www.flheritage.com/kids/symbol.cfm?id=17 

     In North Queensland, Australia there is a location known where a lot of moonstone can be found. This location is Moonstone Hill. There is a path for walking that leads up to the hill, and this path glimmers with pieces of moonstone. The typical moonstone found on Moonstone Hill is colorless, however, there have been specimens found that have a milky tint, or a yellow tint, and some even with a blue adulorescence. Many people go to Moonstone Hill to mine for the gemstone. It can be found in the topsoil along the sides of the hill. However, the more experienced fosscikers usually dig for moonstone at the top of the hill.  

Description: http://t1.gstatic.com/images?q=tbn:ANd9GcQHL5MnZ7b4eN3R-S-rU8eHhsyOsladWYS03o41M05w8rLPtXR9d9RvqiDpUA Description: http://www.australiangemmologist.com.au/images/moonst06.JPG

http://www.australiangemmologist.com.au/moonstone.html  

Formation of Moonstones:

     Since moonstone is a feldspar, this means that it contains not metal or ores. It is formed when gooey magma starts to cool down and the minerals that the magma contains become concentrated. When water combines with the magma it slowly cools over millions of years which forms crystals within the rock. Moonstones, like many other gemstones today, can also be reproduced in a gem laboratory. Many of the unique qualities remain the same, but there is a lack of imperfections to these stones that would be found in a natural moonstone. This makes the lab-created moonstone, like other gemstones, much less expensive.  

Natural Moonstone                 Lab-Created Moonstone

Description: http://www.mineralminers.com/images/moonstone/gems/moonstone.jpg  Description: http://reddeerdesignsonline.com/images/1171818391.jpg

http://www.mineralminers.com/html/moojlry.stm & http://reddeerdesignsonline.com/Tur-ms-Brac1.html 

The Moonstone’s Luster:

     Moonstones are best known for their distinctive properties. The adulorescence of the moonstone is what makes it the most special. This is the ability of the gemstone where light enters into the crystalline structure and bounces back and forth creating a moon-like aura that makes it gleam. The structural pattern of the moonstone is the reason for this occurrence which is caused by the layer effect due to the presence of tiny inclusions from a separate feldspar in the main material. Since the moonstone is made up of potassium aluminum silicate, inclusions of sodium feldspar in the potassium feldspar create that layer. This is what causes that rainbow effect seen in many moonstones; these colors mixed into the main gemstone include white, blue, or even a blue-orange color. The host mineral of the gemstone can be found in many different colors. These colors include yellow, brown, green, multi-colored (or rainbow), and the more popular, blue.

 

Description: http://www.moonstones.com/images/moog133.jpg

http://www.moonstones.com/moonstone_information.html

Description: Moonstone Gems Description: Moonstone Crystals

http://www.ajsgem.com/gemstone-information/moonstone-106.html 

Magic of the Moonstone:

     The moonstone is one of the most magical looking gemstones. With its many changing colors and the glow from it that resembles the moon makes it look like it has enchanting powers. The Romans believed that the stone was formed from the frozen moonlight because of the beautiful shimmer that it gives off. The moonstone is quickly related to goddesses; those goddesses include Diana, Hecate, Artemis, Hera, and Selene, the moon goddess herself. In fact, ancient Greeks called the moonstone “Aphroselene” after both Aphrodite, the goddess of love, and Selene, the goddess of the moon and it was thought that the best time to use the moonstone was during a full moon to make this gemstone its most powerful. Because of its association to the water, moonstone also has said to have the power to protect those at sea. It was given the name “Traveler’s Stone” due to this and then was also said to protect those who traveled during the night, especially during a new moon. Both Indian and European legends thought that the moonstone would make two people fall passionately in love with each other when the moon is high in the sky and they were both wearing the stone. They also thought that it would bring bitter lovers back together. However, the Indian culture also believed that moonstones were sacred and brought mystical dreams and visions when people wore it to sleep. During the middle ages people believed that if you looked into a moonstone you were able to see the future. In the Middle East the stone is said to bring about fertility and to protect both the woman and child during a pregnancy. Because of this myth some women in the Middle East will still sew moonstones into their clothes in hopes to become pregnant. In other regions of the world it is believed to bring about good fortune to those who wear the moonstone. It is also said that it will help to calm emotions of fear and help relieve pains from hormonal and menstrual uneasiness.  

Description: http://skywalker.cochise.edu/wellerr/mingem/gemtl/moonstone/6moonstones-rainbow-vista461a.jpgDescription: http://skywalker.cochise.edu/wellerr/mingem/gemtl/moonstone/6yy-moonstone-peach1-rakhi.jpg

Photos courtesy of Roger Weller/Cochise College

 

Moonstone Properties:

Properties of the Moonstone

Chemistry

Orthoclase Feldspar and Ablite

Chemical Formula

KAlSi3O8

Crystal System

Monoclinic

Hardness (on MOHS scale)

6

Refractive Index

1.520-1.525

Specific Gravity

2.56-2.62

Luster

Pearly

 

Description: http://skywalker.cochise.edu/wellerr/mingem/gemtl/moonstone/6yy-moonstones5-vista.jpgDescription: http://skywalker.cochise.edu/wellerr/mingem/gemtl/moonstone/6moonstone-pink-katmandu589a.jpg

Photos courtesy of Roger Weller/Cochise College

 

Works Cited:

http://australiangemmologist.com.au/moonstone.html

http://crystal-cure.com/moonstone.html

http://gemfossicking.com.au/moonstone_info.html

http://gemstone.org/index.php?option=com_content&view=article&id=126:sapphire&catid=1:gem-by-gem&Itemid=14

http://geology.about.com/od/regional_geology/ig/stategems/statemoonstone.htm

http://shoppeatthemistymoon.com/blog/?p=365

http://www.ajsgem.com/gemstone-information/moonstone-106.html

http://www.controverscial.com/Moonstone.htm

http://www.ehow.com/about_6310151_moonstone-created_.html

http://www.flheritage.com/kids/symbol.cfm?id=17

http://www.induruwabeachresort.com/front/content.php?id=18&type=3

http://www.mindat.org/min-2774.html

http://www.modernjeweler.com/web/online/Colored-Gemstone-Gem-Profiles/Moonstone/1$522

http://www.theoi.com/Titan/Selene.html

 

Images Credited:

http://australiangemmologist.com.au/moonstone.html

http://reddeerdesignsonline.com/Tur-ms-Brac1.html

http://skywalker.cochise.edu/wellerr/mingem/gemtl/moonstone/faceD.htm

http://skywalker.cochise.edu/wellerr/mingem/gemtl/moonstone/moonstone17.htm

http://skywalker.cochise.edu/wellerr/mingem/gemtl/moonstone/moonstone19.htm

http://skywalker.cochise.edu/wellerr/mingem/gemtl/moonstone/moonstone3.htm

http://skywalker.cochise.edu/wellerr/mingem/gemtl/moonstone/moonstone7.htm

http://www.ajsgem.com/gemstone-information/moonstone-106.html

http://www.flheritage.com/kids/symbol.cfm?id=17

http://www.modernjeweler.com/web/online/Colored-Gemstone-Gem-Profiles/Moonstone/1$522

http://www.moonstones.com/moonstone_information.html