Fire opal is a transparent to translucent opal with warm body colors of yellow to orange to red.
What do fire opals look like.
Opal is a hydrated amorphous form of silica sio 2 nh 2 o.
Fake opal or synthetics will usually be too perfect and look man made.
Opalescence is often used to refer to play of color but the term should only be used to describe the milky iridescence of common opals which do not.
Triplets are often glued on to a black plastic glass or vitrolite backing.
Its water content may range from 3 to 21 by weight but is usually between 6 and 10.
Fire opals like other opals are relatively hard rating a 5 5 to 6 5 on the hardness scale.
Crazing looks like multiple crack lines.
The orange stone is about 7 x 9 millimeters in size and was mined in oregon.
A natural opal will have less systematic patterns.
The fire opal is a term not commonly used within australia but most famous source of fire opals is the state of querétaro in mexico.
Fire opal is a term used for colorful transparent to translucent opal that has a bright fire like background color of yellow orange or red.
This can confuse new opal buyers.
Frank this is a typical example of a black or dark opal from the mintabie opal field in south australia north of the coober pedy mine.
Crazed opal is mostly kept as specimens or collectors pieces.
The orange and yellow stones have a sleepy translucence while the red stone is semitranslucent almost opaque.
During winter a wood fire would warm up a room and cold water was splashed repeatedly on the rough.
Because of its amorphous character it is classed as a mineraloid unlike crystalline forms of silica which are classed as minerals it is deposited at a relatively low temperature and may occur in the fissures of almost any kind of rock being.
It is fine if the opal feels like this.
Its a lovely piece.
Although it does not usually show any play of color occasionally a stone will exhibit bright green flashes.
Fire opal typically exhibits a hazy or cloudy appearance which is a result of slight opalescence adularescence.
Look at the back of the opal does it look or feel like a kind of hard black or grey plastic.
Doublets are a little more difficult to identify as they often use a natural potch black colourless opal or ironstone the brown boulder opal host rock backing.
Just clean the back up a bit but dont cut it two thin.
Ethiopian opals are mostly hydrophane and do have a waxy different feel compared to other opals.
Not sure of the quality.
Fire opal does not exhibit much play of color like other varieties of opal.
Crazed opals can be treated with opticon which stabilises the opal.
Like the traditional opal fire opals can occasionally display signs of iridescence in very bright light.
Transparent specimens have a good luster.
Look closely at the pattern in the opal.
Some people are confused when they hear the name fire opal.
Fire opals have a very low density lower than that of glass with which it is sometimes confused.
It may or may not exhibit play of color the color of fire opal can be as vivid as seen in the three stones shown here.
They are not recommended for use in jewelry.
Its perfectly ok to leave the white sandstone type material on the back as long as you clean it back to reasonably smooth.
