Opal is an amazing stone both magically and mineralogically. Since it doesn’t have a crystalline structure, it is not classified as a mineral but a mineraloid. Opal is amorphous and made of hydrous silicon dioxide and can contain up to 21% water, though it usually contains 6%-10%. It is found in fissures of rock, usually limonite, sandstone, rhyolite and basalt. 97% of the world’s supply of opal comes from Australia.
Because of opal’s unique nature, individual opals can vary widely in appearance from one another. Opals come in a variety of colors and many display flashes of other colors within as well. Types of opals may be named for their color, the play of colors within, the location of their origin, or the other minerals they accompany.
Precious opals display a play of color caused by tiny silica spheres arranged in a network. As the light passes through the spheres it is diffracted like a prism and displays different colors based on the arrangement of the spheres. As the angle of the light source in relation to the stone moves, it creates brilliant flashes of changing color.
Common opal, also known as “potch” does not display this effect because the spheres within are not arranged in a manner that promotes this play of color, but all opals have opalescence, a pearly luster. While common opal isn’t as flashy as precious opal, it can also be a gorgeous stone and is useful for jewelry and magick.
Fire Opal is the name given to opals that display “fiery” colors such as red, orange and yellow. These may be transparent or translucent and they do not show to play of color found in precious opal.
Boulder Opal is a rock of another type, the “host rock”, with opal within it. Since opal forms in fissures in rocks, this is common and can be very lovely. Magically, the energy of the host rock can be amplified by the presence of the opal. The opal inside boulder opal can be of any sort.
Black Opal is any dark-colored opal. This includes dark blue.
There are many more types of opals. Some excellent pictures of various types of opals can be viewed at http://geology.com/gemstones/opal/
Opal Correspondences and Lore
Opal is the birthstone for the month of October.
It is a traditional gift for the 13th wedding anniversary.
Opal is the national gemstone of Australia.
Black Fire Opal is the state stone of Nevada.
Most opals will fluoresce under a UV light. Synthetic opals will not.
Opal for Magick
Opal contains the energy of all the elements and can be used for just about any magical application. It also amplifies the energy of anything it is used with and can amplify the energy of the wearer. However, opal can be unpredictable and should be used with a bit of caution.
Opal set in gold and worn on the right index finger makes a good talisman for those who must work with other people. It enhances foresight, empathy and confidence and helps the wearer influence people to his point of view.
Opal is said to aid in invisibility spells and can be used as a talisman to help your actions go unnoticed.
Fire opal is said to help protect from injury from natural disasters.
Any opal can be used as a scrying stone and to enhance psychic abilities, to increase intuition and inspiration and to help recall past lives.
It is said that opal is a very good stone to wear for general luck, especially for those born in the month of October. Opal is a stone of inspiration, imagination, and emotion and may prove valuable to writers, musicians and artists. However, opal can magnify emotions and mirror the emotions of others and can help break down inhibitions. Therefore, it may not be the best stone to wear on a regular basis.
Caring for Your Opal
Opal is a very soft and sensitive stone. Because of its high water content, it is subject to damage by extremes of temperature and can be easily chipped or scratched. Some recommend storing opal in water when not in use.
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