Opal Information

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OPAL
Our opals are affordable opals and not those exceptional opals you see only in pictures or in museums. Each opal we have available has its own character you can cherish forever. Usually the higher price per carat indicates the flash is more lively and colorful, more evenly distributed, a rarer base color, or have an unusual characteristic, or have any combination thereof.

Common opals do not have the iridescence or flash (also called "fire") that is characteristic to precious opals. They are generally opaque, translucent, cloudy, and have a rather dull, pale, unattractive color. The spheres of silica that compose common opal are too large or not set in orderly arrays which are the key factors for transmitting the iridescence (diffracted color play) normally seen in precious opals. These opals are plentiful and have very little value. Rarely would we have opals of this nature on our lists.

Precious opals have the characteristic iridescence or flash (also called "fire") that is normally associated with opals. All of the following are different classifications of precious opals that we usually have available for purchase:

Regular opals are usually white base precious opals which are the more common variety of precious opals. They are the least expensive group of precious opals.
Black opals are much more rarer than white opals and demand a much higher price. A black opal can be of any three grades of base color varying from "Black 1" which is a dark gray; to "Black 2" which is a lighter black but not a true black; to "Black 3" which is a true black color.
Semi-black opals have a base color that varies from a medium gray to a dark gray but not dark enough to be called a black opal. The price of these opals are usually less than black opals.
Gray opals have a base color of medium gray to a lighter gray. The price of these type of stones are usually less than the semi-black opals.
Crystal opals are transparent enough to read text through them. Their price values are usually less than black opals and sometimes even less than white base opals.
Semi-crystal opals are translucent or transparent enough to be able to see a dark thick line through them but not clear enough to read text through them. These opals usually cost less than crystal opals.
Black crystal opals have the characteristics of both black opal and crystal opal. The price will be in the range between black opals and crystal opals.
Gray crystal opals have the characteristics of both gray opal and crystal opal. The price will be in the range between gray opals and crystal opals.
Hydrophane Opals The precious variety have the ability to absorb water and become transparent. After releasing water they become opaque again. This process can take place within a few minutes of immersing the stone in water or reversing it by removing it from water. This phenomena can take place without damage to the stone and has very little affect on color flash. These opals are some of the most interesting and intriguing. Most of these precious variety of hydrophane opals come from Virgin Valley, Nevada.
Sometimes "Hydrophane" refers to opals that are dual until wet with water. These dual hydrophane opals are not considered precious and are usualy found in Australia.
Boulder opal results from the splitting of a seam of opal running through the parent rock or boulder. The resulting cut, shaped, and polished piece will have opal as its face and the host rock material, usually ironstone, for its base. These opals were tossed aside or sold very cheaply in the past, but today they demand a high price sometimes as much as black opal. Almost all of these opals are from Queensland, Australia
Matrix opals may consist of (1) a porous opal from Andamooka, South Australia which is often dyed black and/or treated with Opticon or similar resin type fillers and stabilizers, or (2) an ironstone from Queensland, Australia containing veins of precious opal.
Contra luz opals are very much like crystal opals but have the ability to also create color flash as light passes through from the opposite side. This unusual characteristic makes these opals more interesting and therefore may demand a higher price. Contra luz opals may also have the flash normally resulting from reflected light in addition to its characteristic flash.
Crystal with matrix is composed of crystal opal material naturally backed by or surrounded by the natural matrix or Rhyolite material after it is cut, shaped, and polished. The value of these opals vary in price depending on the rarity and esthetics of the piece. Most Mexican varieties are inexpensive.
Fire opal is an orange or reddish opal from Mexico that has no play of color or iridescence and is usually faceted. The term "fire" is a misnomer. It implies that there may be fire or iridescence in the stone when there isn’t. Its name was derived from its base color which is the color of fire or a flame. These stones demand a high price when faceted from highly transparent reddish orange color material.
Doublet opals are composed of two layers. They usually consist of (1) an opal top fabricated over opal matrix material, potch (common non-precious opal), basanite (a fine grained black jasper usually from North Carolina), jade, or black onyx or (2) a glass or quartz top over a precious opal base. The value of duplets are usually one-fifth to one-tenth the value of the opal if it was a solid and not an assembled composite.
Triplet opals are composed of three layers. They usually consist of a very thin opal slice sandwiched between a glass or quartz top and a potch, basanite, jade, or black onyx bottom. These opals usually sell for about one-tenth the value of the opal if it was a solid and not an assembled composite.

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