Synthetic opal: description, difference from natural, application

2024 Author: Priscilla Miln | [email protected]. Last modified: 2023-12-16 00:21

Jewellery has always been a sign of we alth of their owner. But there is nothing wrong with imitation stones if they are sold at their actual cost. Only the modern craftsmanship of jewelers, as well as the variety of types of stones, encourages you to ask a lot of questions when buying jewelry.

Opal and its types

Some opals shine in different colors, shimmering in the light, while others do not cast overflows. Naturally, the beaming nuggets are more expensive, but every variety of opal is good enough.

Varieties of opals, taking into account color, brilliance, transparency, hardness, impurities are as follows:

• Semi-opal, opal jasper. The process of its origin is associated with the weathering of silica silicate rocks.
• Wood opal. It has the structure of wood, formed by replacing wood with opal.
• Silicon tuff. A porous type of stone that forms in hot springs.
• Triple, polished slate. Loose mass formed as a result of deposits of microorganisms.
• Noble. Gemstone, transparent or translucent, white, yellowish, blue, black shades.
• Ordinary. Semi-precious nugget of various degrees of transparency, without overflows.
• Fiery. A translucent variety of opal, without mother-of-pearl play, having shades of yellow and red. Mined in Mexico, Turkey, Kazakhstan.
• Black. An expensive type of stone of a dark shade. Its base is black, dark blue, purple.
• Boulder. Interlayer in ferruginous rock, rhyolites, bas alts.
• Wax. Has a waxy yellow, rich amber hue.
• Gialitis. A transparent watery gem with vine-like crusts on mosses and lichens.
• Hydrofan. Water stone with a porous structure. Filled with moisture, it becomes translucent with overflows.
• Girasol. Translucent stones with blue reflections.
• Irisopal. Solid color, colorless to brownish.
• Cacholong. It is a mixture of chalcedony, quartz, porcelain opal, milky, white.
• Peruvian opal. It has amazing transparency. Stones of pink, bluish, blue shades.
• Green. Opaque stone, a bit like jade, but brighter.
• Chrysopals. Light green opaque stones.
• Prazopal. Pink, blue, bluish opals.

Natural stone

Opal belongs to the quartz family, but, unlike it, does not havecrystal structure and contains a significant amount of water. The maturation period of the stone, known from the first decades of our era, lasts a whole century.

The high cost of natural opal is due to important factors such as:

1. The rarity of the gem. Opal jewelry belongs to the premium category. Mining sites of the mineral are more concentrated in Australia (90%) and Ethiopia (10%), it is also found in America and Brazil. Of all the nuggets mined, most of them are white crystalline opals. About 5% are black opals, expensive and noble stones - 1-2%.
2. The capriciousness of a nugget. Natural opal can become covered with cracks even in the process of its extraction from the bowels of the earth. Some minerals do not tolerate processing and polishing. Of the many parts of the mineral, only a small number of stones can become ornaments.

It is hardly possible to collect a string of beads or a bracelet with stones of the same properties and size, so the demand for the production of artificial minerals is growing.

How to tell a real opal from a fake?

The more expensive and beautiful the stone, the more temptation to create its analogue, and the more questions consumers have when buying a product.

Here's how to tell a natural opal from an imitation:

1. An unusual but accurate way to check the authenticity of an opal is to put a stone on the tongue: if it is artificial, it will stick, which will not happen with a real nugget.
2. Influenced by sunlight naturala stone lying in the palm of your hand will color it in a rainbow color. If there is a fake in front of the buyer, there will be no such overflows.
3. Patterns. If the opal is real, the patterns in its inner part do not repeat, the color of the mineral remains uniform. If the stone is artificial, you can observe a change in its brightness, and the patterns will be the same.
4. Layering. Sign of synthetic opal. Layers are strips, pieces attached to each other. A natural mineral cannot have a similar structure.
5. Transparency. If the stone has a pure, milky white color, this is a property of natural opal. If a darker base is visible, the stone is synthetic.
6. Bubbles. If you can look at the stone under a magnifying glass, the artificial stone has miniature cracks filled with air. These bubbles are formed due to temperature differences during glass processing.
7. Stones of very intense colors - hot pink, poisonous green - are usually fake.

Gemological examination is the most reliable method of verifying the authenticity of an opal, however, it is paid. But the described methods will help to exclude fraud by unscrupulous suppliers.

Cost

Opal is a very beautiful mineral, and the demand for it is constantly growing. The cost of a processed stone weighing one carat has a cost of about 100 dollars. The price of an opal rises as its size increases and almost equals the value of gold. A three-carat opal can be purchased for $200, a six-carat opal for$300.

Natural stone beads will cost between $150 and $450. The price of earrings with opals depends on the material of the frame, the type of gems and additional elements that make up the products. The type of mineral will also affect the value of the jewelry: black is considered the most expensive. A bracelet made of stones of natural origin is estimated at 7,000 or 20,000 rubles, depending on the conditions of the manufacturer.

Since there are very few natural stones in nature and consumer demands cannot be met, an artificial stone has appeared on the market. Synthetic origin significantly reduces the price of opal. And the methods of its production are so improved that the quality of products remains quite high. Its advantage is that artificial opal is a more durable structure and gives an idea of the technologies used.

Suspiciously low cost of synthetic opal indicates a low quality fake. A crumb of stone costs 130 rubles per gram.

Production of artificial opal

After studying the structural features of the stone and thanks to the electron microscope, it became possible to produce synthetic opal. The first technology was patented in 1964 by Australian scientists A. Gaskin and P. Darre.

And in 1973, under the leadership of Pierre Gilson, a Swiss company provided a large range of imitation opals, the cost of which was several times lower than natural ones.

The synthesis of opals is carried out throughmultiple steps:

• By hydrolysis of organic silicon compounds in a solution of water, alcohol and ammonia, globules of the same size are formed, after which they are subjected to the process of centrifugation in the resulting suspension.
• In the next step, the material is compacted by impregnating with silica sol and calcined in an autoclave (at 600 °C) to give strength.

Opal is also grown in the laboratory. Japanese and Australian jewelery companies, like the French discoverer of the technology, also favor stone synthesis.

Many materials with plastic and glass in their composition can have an external resemblance to opal. A high degree of porosity makes it possible to color artificial stones with various fillers: resins, glass.

Refining

There are artificial minerals on sale, but you can also buy ennobled natural stone. Precious, especially black nuggets, are very rare, so imitation opal is becoming popular.

The so-called doublets are stones on sale, the upper part of which is a transparent structure, and the lower part is a glued dark base. Thus, the appearance of synthetic opal is as close as possible to natural. If you look at the product in profile, you can see the border of the fixation of the two layers. The cost of such jewelry is several times lower than the real one.

Triple technology involves attaching a transparent dome to the base. Additional method - impregnationsmoke. Its particles are retained inside and give the product more brightness.

Refined artificial opal is more expensive than its ordinary imitation. Sellers can inform about the method of making a stone, its composition from two or three parts, but at the same time hide the fact of coloring. It is worth paying attention to the peculiarity of the product that its upper, real and precious layer is not at all deep.

How to take care of the stone?

The gem is quite capricious, and in order for it to retain its qualities and not dry out, it is recommended to wear it constantly on the body. Opal earrings do not need special attention, but if it is a ring, it must be removed when doing housework. At low humidity, the mineral becomes cracked and becomes cloudy. Chemical agents are also contraindicated for opal.

Warm soap solution is used to clean the stone. You can use a non-rigid toothbrush, as well as pre-let the product stand in water. Then the product is wrapped in a damp cloth and laid out under the rays of the sun for several hours.

Given the fragility of the mineral, its handling must be extremely careful. It is better to store opal in boxes and special napkins, which will protect the stone from external influences.

Application industries

Opal is used in the jewelry industry, small fragments - in beauty salons to decorate nails. Polished stone plates are attached over onyx, obsidian, black glass. Due to its low strength, opal was impregnatedartificial resins, oil was applied to its surface, and strong frames were made for it.

Crushed stone and small specimens can be used as decorations for buttons, hairpins, brooches, cufflinks, purses, jewelry boxes and other accessories.

Rocks with opal in the composition - diatomites, tripoli, flask - raw materials for the manufacture of cement and other building materials.

Interesting facts

The variety of beliefs has led to the fact that opal has become a mystical symbol in magic, alchemy, and is common in jewelry production. The word "opal" is of Sanskrit and ancient Greek origin.

Interesting facts about opal:

• Opals are found in varying amounts all over the planet, and in 2008 they were also found on Mars.
• For some time, tripol was part of dynamite. The largest and most valuable mineral has a value of $2.5 million.
• Opal is the official symbol of South Australia and the women's basketball team.

Legends of the stone:

• Ancient tales about Zeus contain a story about how, in the victory over the titans, the tears of a deity became opals.
• According to Australian legend, the Creator descended from heaven to pass on his knowledge to people, and his every step on earth was marked with a rainbow color of opal.
• According to Indian legend, the goddess of love, hiding from the persecution of men, crumbled into beautiful stones.

Magic and healing properties

It is believed that opal brings itscalmness for the owner, helps with heart diseases, fainting, stabilizes the central nervous system, eliminates tics and chronic convulsions, improves digestion. The stone protects the owner from the destructive effects of emotions, balances his condition.

If you do not take your eyes off the opal for a long time, vision improves, intraocular pressure decreases, the pupils acquire a magnetic radiance. Lithotherapists recommend the use of opal for depression, insomnia, to recover from stress.

In India, they believed that opal enlightens the mind, destroys fear and negative thoughts, and improves relationships within the family. Among Europeans, this stone has become a symbol of friendship, hope, happiness, love. An opal amulet was considered a strong protector from the evil eye, it revealed knowledge of the future. Its magical properties also include attracting success in everything, developing clairvoyance.

According to the esotericists, black opal can harm a person with a weak character because of his desire for vicious pleasures, since along with various influences it awakens passion. This mineral sharpens analytical abilities, activates creative self-realization.

The white stone develops the spiritual principle, brings harmony and peace. For a talented person, opal becomes an assistant in the development of abilities, helps healers and psychologists, developing patience and compassion. And the setting of gold greatly enhances the properties of the mineral.

Fire opals reveal masculinity, sensuality, determination, self-sufficiency. Blue and blue mineralshelp in achieving goals, in accumulating the necessary energy in order to concentrate it in the right direction.