Opal Necklace

by Sanjana Sethiya

Opal just a gem is so beautiful, if it is converted into some exclusive jewelry’s then no looking back for both the buyer’s and seller. Necklace, earrings, nose rings, lockets made of opal are very beautiful and look very stunning. Many go flattered when they visualize Opal necklace.

Opals were first found on earth when dinosaurs roamed the earth. It is as old as the olden civilization. Due to its shine and artistic colors it was used by kings, astrologers and rich personality. Opal was much used by astrologer in order to forecast the future events. It is also termed as an ancient stone. Opal as a gem did not got its importance earlier but pleased to the eyes of the seeker due to its rainbow color. In olden era, Opal had no value. It was treated as a common stone with flashing color. As time passed, Opal importance, value, and moreover demand has raised up to a very huge height.

For being the only gemstone which has unique ability to reflect and refract the white color or sunlight into all the beautiful colors of rainbow. Opal is a beautiful multi-colored gemstone, which is a bit costlier. Opal is related to crystal cousin’s quartz and agate. Opal is one among the few gemstones, which are formed on sedimentary rocks where water is one of the main elements of it.

Opal stands for the month of October. Those who are born in this month should wear Opal to achieve success in their respective career/field. One who wore lockets, necklace studded with Opal increases the memory of the wearer and earrings studded with Opal enhances of the beauty of the wearer. So one who wants the combination of both beauties with brains can be achieved by wearing/possessing Opal jewelry. It is always misunderstood gem. Most jeweler’s carry on their business of diamond and gold. And many are not aware of the existence of other gems that are also beneficiary for human kind in various forms. One among them is Opal.

One question may strike in buyer’s mind. How can we know about a good gem? Whom can we trust? How much does it cost? And the answer is very simple, knowledge. If one want to buy any gem or precious stone, they should first have knowledge about the gem and knowledge of how this beautiful gem translates into market value, which will allow you to buy Opal with confidence. There is a small quotation, “trust thy knowledge, not others”, this will help the buyer’s to purchase authentic and good Opal stone.

Opal just a gem is so beautiful, if it is converted into some exclusive jewelry’s then no looking back for both the buyer’s and seller. Necklace, earrings, noserings, lockets made of opal are very beautiful and look very stunning. Many go flattered when they visualize Opal necklace. Now-a-days Opal necklace are worn by various people on various occasions. Opal likes to breathe in the fresh air, therefore it can be worn on any part of the body. It even likes contact with the skin. Therefore they can be worn on neck, ears, fingers.

Opal stone are not found in large and are found only in few places in the world. Australia is the main supplier of Black Opal, which is the famous Opal in the world.

Buyers should keep in mind the following factors while purchasing opal necklace/jewelry’s.
1. While purchasing Opal necklace, valuation and identification of Opal should be undertaken. There are various factors’ which will help the buyer to buy the real and good Opal jewelries. They are as under. A) size and shapes of Opal
B) Color and patterns
C) Clarity/brightness
D) Valuing Opal
E) Types of Opal

2. Opal evaluation plays an important role while purchasing it.
3. Opal should be tested in sunlight, if direct contact falls on Opal it produces rainbow color, which is enough to certify/clarify, the doubts regarding Opal.
4. Different types of Opal are found. Buyer should have a keen knowledge regarding this factor.

There fore, these factors help the buyer to identify the good Opal.

While cleaning Opal jewelry’s/necklace, buyer should keep in mind that it should be cleaned only on plain water and no chemical, machines or any other mode to be used to clean them. Opal should not be ever cleaned by glycerin, because Opal contain moister in it, glycerin removes the moisture content in order to avoid this one should be aware of it. Therefore, buying Opal necklace is easy but taking care of it is very easy but one should know about it.

Opal Facts and Buying guide

by Shweta Dhanuka

Its name is derived from Sanskrit word ‘upala’ that means valuable stone and also from the Greek term ‘opallios’ that means colour change. Both these derivations are ideal for this amazing gemstone.

Opal is nature’s astonishing gift to all gemstone lovers and admirers. It is the heartthrob for many due to its magnificent features such as tender shine, attractive colour play and sparkle. Its name is derived from Sanskrit word ‘upala’ that means valuable stone and also from the Greek term ‘opallios’ that means colour change. Both these derivations are ideal for this amazing gemstone. It is the birthstone for those born in the month of August.

It is a royal gemstone. When it is said royal it means this gemstone is very much valuable and expensive thus but obvious there becomes more chances of innocent buyers getting cheated. To avoid these probable mis happenings, buyers are ought to be aware about the gemstone.

Therefore, this article offers the necessary information that would help in the purchase of genuine gems. The facts given here can also be used as the buying guide to evade all the future surprises. Buying opal from internet is not a good option as it is very difficult to take the pictures of the stone. The photographs are quite exaggerating than the real worth of stones offered for sale. Also the colour seems different from the reality. Then always look for a domed gemstone, as such stones are stronger and less prone to break off. There are other characteristics like colour, cut, varieties etc that should be closely studied before handing over the cost of the stone to the seller. These all are conferred one after the other to endow the buyer with necessary details.

Varieties – This gemstone is available in two different types. These types are differentiated on the basis of colour play.

Common Opal – Those stones that lack the colour play are common opals. It is also called as ‘potch’. As almost all the people seek opal that exhibits colour play, the value of this type is very less. Only when it occurs as colorless it is taken into some consideration. It is regularly treated to make the stone attractive.

Precious Opal – Precious opal consists of spheres arranged in uniformity thus it display fine-looking colour play. Spheres are transparent hard crystals that are set within the stone in three-dimensional structure. Thus, when light falls on it, all the spheres produce different colours resulting to rainbow like play of colours.

Precious opal is found in three different forms and few different varieties. All these are real gemstones only. Forms are classified into three on the basis of the structure while varieties are distinguished from each other on the basis of the colour. First lets discuss the forms followed by the varieties. (From now, the text only refers to precious opal and not the common opal)

Solids – Solids are one single piece and are very expensive.
Doublets – It is made up of two pieces and are priced less than the solids. It is cemented with the natural black backing. Sometimes, common opal is used as the backing.
Triplets – This form is made up of three pieces thus called as triplets. These are the cheapest form. Like doublets it is too cemented with natural black backing and also a crystal cap is attached on the top of the stone to give it a dome shape. For backing purpose at times, common opal is used.
All these forms are widely used for making jewelry and sometimes for the ornamental use as well. The different varieties can be of any of these forms or might exist in all three forms too for example solid black opal, doublet black opal or triplet black opal. It is nature’s creation thus nothing can be standardized or fixed. There are many varieties of this marvelous gemstone but here we discuss only few important ones.

Black Opal – It is most-sought-after variety of opal. It is treasure all over the world because in this particular colour, the colour play is displayed at its best. It comes in all deep and dark colour variations. The natural basic black colour highlights all the different colours in the best possible way therefore the colour play are overwhelming in this gemstone. Solid black opal is the most valuable thus, priced very high.

A variety known as “Andamooka Matrix” looks absolutely same as black opal but lacks in the quality when compared with the natural black opal. Those who cannot afford a genuine black opal can buy this variety as it is priced much less. Buyers should make the purchase only from the genuine and reputable dealers who would clearly mention about the two of these varieties and their respective prices.

Semi-Black Opal – The body colour in this stone varies from grey to almost black. It gives more of a smoky look. It is easily available in many areas.

Crystal Opal – It comes in lighter and delicate shades on the top. Many layers of colours are seen in it. All colour variations are available in this variety. Light colours make this stone translucent. It comes after black opal in the priority list of pricing.

Boulder Opal – It possess natural brown body colour or the back that appears black from the front. It is too available in all colour variations. Often it possesses rolling surface and ironstone inclusions. It can be given any innovative cut. It is ideal for earrings.

White Opal – Last but not the least, this variety exhibits scattered colours and is opaque in nature. It is also called as Milky Opal and is very economic to buy.

Harlequin Opal – It is most rare and expensive variety. It comes in irregular tile pattern with black body colour. It looks very similar to that of the widely created man made opal known as ‘mosaic opal’. Buyers need to be vigilant at the time of purchase of this variety else they might land paying the price of Harlequin opal and take away mosaic opal.

Fire Opal – The basic colour is orange or red, both colours are related to fire thus, this variety is named accordingly. It is mostly procured from Mexico. Fire opal is an opal gemstone in itself and not just an imaginative term used to describe the colour play of any other variety of opal.

Colour – Amongst all the gemstones, opal is the only one exhibiting all colours in one single stone. The brightness and pattern of colours varies from one stone to another. Every single stone is unique in its own way. The basic colour often referred, as body colour can be black, white, colorless, pale yellow, blue, pale red or gray.

The colour play means that the stone exhibits different colour mix when light falls on it. With the change in angle or direction of the light the pattern of the colours also changes, thus called as colour play. Varied colours are seen when the stone is slanted or rotated. This display of colours is so exclusive that it is often discussed in imaginative terms like flame opal, lightning and peacock opal, church window and many more.

Clarity – This captivating stone possess vitreous to pearly luster and is transparent to translucent in nature. It consists of inclusions and flaws just like other semi precious gemstones. These inclusions are the negative trait hence, deteriorates the real worth of the stone.

Cut – It is a very important characteristic as the beauty of crucial feature i.e. colour play of the stone is dependent on cut. The cut of the stone finally reveal its magnificence. First, the cutters remove the inclusions present in the stone with the diamond cutting wheel then any soft dome shape is given in order to bring out the fine colour play. After the cutting the finishing is done using the sandpaper and finally the polishing is done with the help of wet leather wheel. The jewelry designers and buyers can get the desirable cut or the shape of this striking stone. Oval, circular and round cabochons are preferred most as in these shapes the colour play is displayed at its best. Few other popular shapes are teardrop, square, rectangle and triangle etc. In order to augment the opalescence, solids and doublets are cut and polished with a convex dome or curved top while in triplets the crystal cap is cemented to create the dome so that it covers the plane top of the stone.

Carat weight – It is found in thin layers, as large pieces are rare in nature. After the initial gemstone processing, it is transformed into many sizes so that it suits the varied jewelry designs and also reaches as many people as possible. Some people have the budget restrictions so they can opt for smaller stone sizes with less carat weight.

Price – Price is determined on the basis of basic colour, cut, clarity, carat weight and source. Besides these price determinants, the most vital characteristic to ascertain the new value of the gem is the colour play. More intense the colour play more is the cost of the stone. A good cut, lesser inclusions, high carat weight and stone from Australia are zenith of all the factors that increases the value of the stone in terms of money. When these reduce the value also reduces.

Occurrence – It is a water rich mineral, composed of silica gel. The percentage of water varies from 3% – 20%. It is formed randomly when layers silica rich water precipitates at low temperature in the cavities and niche of sedimentary rocks. Gradually the gel transforms into the stone known as opal.

The incredible play of colour is exhibited by the gemstone due to the presence of small spheres in the silica gel that causes interference and refraction appearance. Silicon and oxygen chains are packed in the spheres and these are uneven in size and incoherent in concentration. These are set in a compact structures thus, when ray of light falls it dissects the light on its way through the stone resulting in the awesome colour play. As per the size of the spheres within the structure, changeable colours of the gamut are diffracted. With the increase in the consistency of the spheres position, more intense and brilliant would be the colour play.

Source – The prime source for this colorful gemstone is Australia. More than 90% of the total gem in the entire world’s market is procured from this country. Mexico, Ethiopia, United Kingdom, Czech Republic, Brazil, Honduras and few states of USA together contribute to the remaining 10%.

Grading – Grading for this superb gemstone is done on the two factors viz. colour and clarity. Bright and deep colours along with minimum flaws are graded as finest quality while pale colour with too many inclusions is considered as poor quality. These are the two extreme grades. The medium quality means stones possessing combination of the two factors in medium proportion or one factor at its best while other factor is not so good and vice versa.

Enhancement – The stone surface is treated with colorless artificial resin to improve the life of the gemstone. Occasionally, the stone is may be re-hydrated with water or special oils to regain its lost opalescence. Unfortunately this treatment does not last for a longer durations. Further, enhanced stones should be avoided because in case of opals no treatments leave permanent change. Therefore, it is better to buy a doublet or triplet instead of an enhanced solid stone.

Imitations – With the modern treatments synthetic opal is produced that exhibits satisfactory colour play but are much cheaper than the original ones. In case someone cannot afford a real opal then it is fine to buy an artificially created stone but the buyer has to be careful with respect to the price. Few cunning dealers would sell synthetic stones at the price of genuine gemstone. At the time of making the purchase of true gemstone buyers have to be very cautious of the stimulants and also the synthetic stones. Stimulants are poor quality glass or plastics that are stained in bright colours and sold under the trade name “Slocum Stone”. In order to avoid the future shock, buyers must make the purchase from the reputed dealers only.

Uses – It is extensively used for making astounding jewelry items. Necklace along with matching earrings and rings is quite commonly seen worn by women in all parts of the world. It is gets along very well with diamonds especially the black opal. In most of the designs opal takes the prime position and diamonds are placed encircling it. Metal used can be 18K yellow gold, 18K white gold, platinum and sterling silver. However, for opal jewelry yellow gold is idyllic and it also doubles the power of the gemstone. In conjunction with the solids, doublets and triplets are widely used in jewelry making. At the time of purchasing the jewelry one should check the stone from the back of the jewelry to know whether it is triplet. If it is triplet then at the back the stone the colour would be pale and some colour variations could be seen. Triplets can be identified but it is very difficult to differentiate between the solid and doublets.
Seldom it is used for making decorative items or for the ornamental purpose. The reason being it is relatively a soft stone. However, cameos and intaglios made up of this stone could be seen in some parts of the globe. Beads are also not very popular.

Precautions – It is a brittle stone, rated 5.5-6 Mohs on the hardness scale. It certainly demands quantum amount of precautions and care. Being a water rich stone, it should never get dry else the colour play is affected badly and the surface would show cracks. To avoid the dryness in the stone, avoid wearing it on hot sunny days, direct exposure to high heat/sunlight. Its jewelry should be worn more often for evenings and even during daytime in winters with this the gemstone molded in the jewelry receives the required moisture from the air. Besides, this gemstone is highly heat sensitive. One should never wear it while taking bath in hot tub, Jacuzzi, swimming pool, sauna or steam room else it would crack. It should also be protected against harsh chemicals present in cleaning agents and cosmetics else being porous in nature it gets damaged.

Avoid wearing opal jewelry while cleaning or gardening as soil and dirt might take off the polish of the stone. Also the claws holding the stones in the jewelry gets loose and then develops a probable chance that stone may fall off. Besides, one must keep checking the claws and the setting of the jewelry items from time to time. If it is loose, either the stone can be seen moving little bit or when the jewelry piece is taken near the ear, after slight rattle one can hear the sound of the stone movement. Cleaning should be done with plain water and soft bristle brush. After cleaning it should be wiped off fully with a soft cloth. These precautions are important for the lifetime preservation of valuable gems and its jewelry.

Beliefs – In past, it was believed that wearing this fascinating gem helps in finding the true love. Also it was considered as an icon of faithfulness and confidence. Women in ancient times used to wear opal to protect their hair from graying. It was largely used for ritual magic. Even in the prevailing era it is still used by magicians to use their powers at the best.
Astrologers recommend different opals for different zodiac signs. Black Opal favors those having the Scorpio zodiac signs while Boulder Opal suits for those having Aeries as their sun sign. It helps in overcoming the depression in life and diverts the energy in improving the positive traits. It enables the wearer to use his/her brain fully.

To own an authentic opal one has to put in lot efforts in studying its different aspects. Well spending so much of energy in procuring a real gemstone is not an expense rather it is an investment for the lifetime. Besides, it is worth when opal makes the wearer look elegant and outstanding in the crowd. Hope you agree !!

Opal Earrings

by Nandita Ray

Opal can be fashioned into any item of jewelry. But the jewelry that really does the opal proud is the earring. Placed on the ear it has the right angle to shimmer and glitter and cast its spell on the wearer and the beholder. The fascination with this stone is never ending.

Jewelry is fascinating. It not only looks fashionable but it is an investment.. The glitter of gold, the sparkle of diamonds, the deep colors of the ruby or emerald, the different hues of the other gems are always enthralling. One of the most enticing precious stone is the opal. Its power to attract and hold a person’s eyes is magical. Its appearance is dramatic. An opal sitting delicately or dangling stylishly, from an ear lobe, mesmerizes one with its brilliant colors. Not just one color but a host of sumptuous colors, rich deep black, flashing blues, striking purples, flamingo pinks, a rainbow of colors. It is a feast for the eyes. Catch a glint of sunray, the opal flashes out myriad colors. The stone has a natural brilliance within it. It looks luminous. Therefore a good opal is as expensive as a diamond.

Opal can be fashioned into any item of jewelry. But the jewelry that really does the opal proud is the earring. Placed on the ear it has the right angle to shimmer and glitter and cast its spell on the wearer and the beholder. The fascination with this stone is never ending. Though it can be fashioned into various types of jewelry, the most popular piece of jewelry is the earring. This is because the earring places the opal in an advantageous place. It is here that it catches the glint of sunlight and as a result shimmers and glitters, casting its spell. The presence of silica gel causes refraction of light and the spheres of silica gel acts like a prism and breaks into the different colors.

In order to bring out the play of colors, the stones are cut and polished into different shapes. Impurities are removed. Sometimes they are covered with a coating of plastic to protect it. When made into earrings, the opal looks smart and attractive. Earrings can be made into studs, knots, hugs, danglers, hoops, prong sets, chandeliers. They can be just opal earrings or can be mixed and matched with either silver or gold. It can be inlaid also.

Black opal which is the most expensive of all opals is rare. The dark background is the perfect way to display the inter mitten colors. Startling blues, a touch of fire red, burnt orange make it a perfect pair to own. This most desirable of all opals comes from the Lightening Ride, in Australia. Mexican Fire opal is also expensive. Worn as studs it looks impressive.

Crystal opal is the second best. It is transparent and the color display has a field day. Rainbow colors, violet, blue, pink, a touch of sea green, maybe even a dash of red, make it a very desirable piece to own. It is truly multi colored. The more transparent it is the more expensive it gets. Worn as a stud or in knots or set in the traditional prong set or as a cluster of grapes, this gem radiates not only warmth but looks like the luminous moon at its very best.

The white opal is opaque. It has different colors too. But it is not very expensive. It is also called light opal. Though it looks stark to the naked eye, under light it has a natural glow, though subdued. The dominant color that flashes out is light blue and crimson. A cluster of opals, a chandelier of opals or inlaid with other gems, complement the opal has an elegance that is understated. An earring looking like this enhances the appearance and makes casual dressing look perfect.

Earrings made with doublet are very common and not at all expensive. This is because a thin layer of opal is fixed to a dark base to provide sufficient depth to the gem. This is an affordable piece of jewelry. An expression of who you are. Wear it as a stud, a swinging chain, a dangler or even as a huge rock sitting on your ear lobes.

Triplet is also a common. It is an opal that is covered with a coating. The coating can be either plastic, or a slice of quartz. Since opal is generally a oft stone it is open to bruises. It is called a triplet because the opal which has been already fixed to a base is now covered. This makes it three tiered. Due to its enhanced color, the gem glows and shimmers like an expensive piece of opal.

Wearing earrings made out of opal is like wearing a Donna Karen piece if not an Armani.

Play of Color

by Nasrina Parvin Khan

A well-known Play-of-color gemstone is opal. Opal is an amorphous from of silica (sio2, nh2o). It is made up of sub microscopic spheres of silica with a little amount of water and air trapped in the spaces between these round spheres.

What is Play-of-color?

Play-of-color is a unique special optical phenomenon. This phenomenon is usually exhibits by the gem opal. The iridescent color effect in opal described as Play-of-color. Color of rainbow can be seen in gems by this optical phenomenon. But the displayed colors are unrelated to the gem’s own body color. So, we can guess that the structural pattern of gem is responsible for this colors creating optical phenomenon. Due to the structural pattern the light interfere or diffract in gems and produce the color phenomenon named as Play-of-color.

Play of color in Opal

A well-known Play-of-color gemstone is opal. Opal is an amorphous from of silica (sio2, nh2o). It is made up of sub microscopic spheres of silica with a little amount of water and air trapped in the spaces between these round spheres. The amount of water in opal may be 3% to 21%. But the precious opals have 6% to 10% water content usually.

Opal is a sedimentary stone. In the time of formation of this stone, oozing water through the earth dissolved in silicates and become rich. The silicates are deposits as minute spheres when the water enters in a cavity.

The transparent spheres of amorphous silica and the voids between them form a 3D grating. This structural pattern is the reason of interference and diffraction of light from the surface or the interior of gems. This property helps to display multiple colors as the angle of incident light changes. The openings act as the diffracting gratings, which split the light into colors, and the layered structure creates interference. The passing light through the stone breaks into various colors. So, we can say diffraction of light take place by layers of silica spheres in its composition and it is responsible for the phenomenon play-of-color.

Shifting patches of spectral colors seen on the surface or in the interior of gem due to the phenomenon play-of-color. Reflected lights from different layers of silicon slightly overlap from sync waves and help certain spectral colors to decrease or remove and reinforce others. So, we get a group of shifting colors that have a trembling on and off effect. The patches of colors moved when the gem is turned around. The effect just like to a bubble with rainbow color, just more dramatic.

Large openings between the spheres do not allowed the light to bend when passing through them. That is why no diffraction takes place and we get common opal. Random shape and arrangement of spheres also produced common opal. Shape, size and regularity of the spheres influenced the colors seen. It also depends on the angle of view. Uniform shape and size of spheres diffract light and help to produce precious opal. On the other hand, smaller size of spheres helps to see more blue and violet colors. But the spheres must be smaller than 1500 angstroms. More reds and oranges are seen with bigger sized spheres. But the spheres should not be larger than 3500 angstroms.

Opal gets the name for its special optical phenomenon Play-of-color. The name came from Greek word ‘opallus’, which means to see a change in color. The quality of opal justified by the number of color exhibited by the gems. The most valuable opal is ‘black-opal’. Which has a strong play-of-color. Different types of colors flashed brilliantly by this stone. Due to dark background color it has given the name ‘black opal’. The colors of black opals are black, dark green, dark brown and others. These gems are transparent to translucent.

There can be seen many other opals, like white opal, crystal opal, fine opal, cherry, water opal and etc.

White opal is transparent to opaque. It has white background with Play-of-color. Crystal opal has no background color with strong play-of-color. This stone is transparent to translucent and lets the light pass through it unlike others. Fire opal is also transparent with yellow, orange, red or brown background color. It may have play-of-color or not. Fire opal with red background color is also known as cherry opal. Water opal is transparent to semitransparent with colorless background. It has little or Play-of-color.

The point of color seen in opal due to the Play-of-color is called as “fire”. The term ‘flash’ used to refer sudden play-of color as stone moved.

Gemologists divided the phenomenon play-of-color in various types, like pinfire, mosaic, flame, peacock etc. A minute, close-set flash of color is called as pinfire. A large, regular, angular, close-set flash of colors is known as mosaic. Sweeping reddish bands across the gem is called flame, whereas blue and green color effect is known as peacock.

See Also: Color Effects in Gems , Asterism, Chatoyancy

External Reference

Play of color info in gemsociety.org
Color Effects in gems

Opalescence effects in Opal

by Nasrina Parvin Khan

The milky, turbid aspects of opal described as opalescence. This phenomenon has been seen in common opal or potch opal. These types of opal do not show a play of color.

There are various kinds of special optical phenomenon, which can be exhibit by the gems. Special optic phenomenon is the unique property of a gem that adds a distinct identity character to the gem. We can identify the gem with this property. Sometimes a particular type of gem shows multiple special optical phenomena, like opal.

We know opal for its play of color. Except play of color, opal exhibits another special optical phenomenon named opalescence.

Usually, people confused with two special optical phenomena in opal. But play of color and opalescence are two different phenomenon of opal.

The milky, turbid aspects of opal described as opalescence. This phenomenon has been seen in common opal or potch opal. These types of opal do not show a play of color.

The term ‘opal’ derives from the Greek ‘opallios’, the Latin ‘opalus’ and the Sanskrit ‘upala’ that means precious stone.

The ranges of color in opal may vary from colorless to white, milky blue, gray, red, yellow, green, brown and black.

Opalescence – How it happen?

Opalescence is caused by the reflection of short wavelength light. Usually it occurs in the blue spectrum. Due to this action of light a milky blue, pearly appearance occurs in opal which known as opalescence.

The structural pattern of opal is the reason of this special optical phenomenon thus the reflection of short wavelength.

Opal is an amorphous form of silica (SiO2, nH2O). It is made up of sub-microscopic spheres of silica with a little amount of water. Air also trapped in the spaces between these round spheres. The amount of water in opal may 3% to 21%.

In case of common opal, the openings between the spheres are comparatively large. So, the light doesn’t have to bend when traveling through them and no diffraction can takes place. But the light scattered instead of diffraction. The scattering effect of light creates a sort hazy effect in the inner particles of opal, which is commonly known as opalescence.

This phenomenon is best admired in a flat cabochon-cut opal (a tall, domed shape gem is called as cabochon). The whole surface of opal exhibits opalescence in this case.

Opalescence Types

We can divide opals in various types according to the color and opalescence type, such as i) white opal with opalescence against the pale gray or pale blue background, ii) black opal with effective opalescence and dark background, iii) harlequin opal with spectacular fancy opalescence outline against different colors of mosaic figures, iv) flaming opal of yellow or red color with spectacular opalescence consisted a fire.

Opalescence is the optical phenomenon, which adds value to the opal and helps the gem belong to the royal family.

Other Optical Effects in gemstones
Asterism
Play of Color
Chatoyancy
Labradorescence
Adularescence
Color Change phenomenon
Special Optic Phenomena

Opal Pictures

by Mark

Opal Pictures