Opals are thought of by many as the most beautiful and exciting of all gemstones. The fascinating play-of-color in which a rainbow of hues dances before your eyes is one of the true wonders of nature.
Opals are a unique gemstone in every sense of the word, from their crystal structure made up of millions of tiny spheres to their transparent, translucent or opaque bodies. They can be a single vivid color or a mix of all imaginable colors, have a light white background or a deep dark backing - the variety is endless.
Describing the color of an opal is not simple. Some opals possess all the colors of the rainbow but never in regular lines or bands - more like an abstract painting or a random composition.
I will attempt to categorize opal colors as best I can.
We have the most common. White opals with a pale or light body tone upon which the kaleidoscopic colors will be displayed.
Then we have Black opals which have a dark body or background for the colors to contrast against in a dramatic manner.
There are also Fire opals which are generally all one color but the color is a vivid and intense hue often red, yellow or orange as the name may suggest.
The variety of opal colors is too vast to go into much detail but please read our article on Opals for more information.
The types of gemstones that fall under the name of opal are almost as endless as the colors they come in.
Just some of the more well-known ones are:
And we could go on and on!
As with most gemstones, it is the color of the opal that is the number one consideration when appraising its price.
Opals are such an irregular gemstone so there will always be different opinions about which is the most beautiful and we all have our own preferences but over the years certain trends have proved more valuable than others.
For example, an opal that has a dominant red color covering much of the gemstone surface will be very highly valued.
As a very general rule, as you move down the color spectrum from red and orange through green to blue the price lessens more and more.
The direction of the color is an aspect not found in many other stones. Because of the crystal structure of opals, some colors will appear clearer and brighter from one angle more than another.
Other factors have to be taken into account of course with color coverage, contrasts between the color and the background, color intensity and so on.
Once an opal has been evaluated according to its color, intensity, play-of-color, coverage and so on it is given a price per carat to calculate the gemstone's total value.
Australian opals can be priced as low as $20 per carat all the way up to as much as $1000 per carat for the finest examples.
Fire Opals reach $15 - $100 per carat and Boulder Opals can be found at prices of $5 - $300 per carat depending on quality.
Usually Opals are not treated other than by cutting and shaping the stone to capture the best color and pattern and then polishing it.
Some opals look better with a stark contrast between a dark background and a bright color up front. To his end smoke can be introduced into the gemstone's pores to darken the stone. For the same reasons, black opals can be treated with a sugar-acid solution.
A totally accepted form of treatment for opals is the doublet or triplet where a thin layer of opal is mounted onto a durable backing and sometimes given a clear top. This protects the very thin and fragile opal material.
All treatments received by any of our gemstones are clearly disclosed.
Where are Opals found?
Australia is the most famous source of opals with around 90% of the world's supplies originating there. Ethiopia has become a significant player in the Black Opal trade while Fire Opals are most often found in Mexico.
What jewelry is Opal suitable for?
Opals have a rating of 5.5 to 6.5 on Mohs hardness scale. This would normally make them a little bit fragile for many types of jewelry items and not suitable for daily wear.
However gemstones such as Boulder Opals and Matrix Opals are still attached to the durable rocks they formed in so are much tougher than the rating would suggest.
Opal couplets and triplets are also designed to be worn on a regular basis.
Large and striking opals cut into interesting odd shapes can help create wonderful and unique jewelry items, especially pendants, brooches and earrings where durability is not such an issue.
Birthstones and Anniversaries
Opals are the birthstone of October and would make an ideal gift for anyone who has a birthday in that month.
An opal is the traditional gemstone gift for the 14th wedding anniversary.