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 !!