About Zlatarna Celje
Zlatarna Celje is one of the largest, best-known jewellery manufacturers with a well-established tradition, quality, and a recognisable brand since 1844.
The value and meaning of the Zlatarna Celje brand are based on our own premium design, the proficiency of our goldsmith experts, and quality materials.
Jewellery is meant to last forever, which is why we are trying to maintain our tradition while keeping up with the times. We are proud of our goldsmith experts who manually finish every piece with love while thinking of our customers. This is how our marvellous jewellery becomes priceless: manual processing makes our pieces completely unique, seeing as our experts are paying attention to every single detail. Zlatarna Celje therefore remains synonymous with premium jewellery.
It is good to know
The products manufactured in Zlatarna Celje are manually finished, therefore deviations may occur in terms of dimensions and the visual aspect of individual products bearing the same nomenclature. Certain discrepancies may also appear in terms of colour and dimensions of precious and decorative natural stones.
Gold
The chemical symbol for gold (Au) comes from the Latin word aurum which means “to glow” or “to gleam”.
Pure, noble metals such as gold are too soft to be made into jewellery, which is why they are combined with other metals. The resulting alloy is a solid solution of two or more metals. The load of gold in the alloy is called “fineness” and means the mass fraction of the gold in the total mass of the alloy, expressed in thousandths. A gold product with a fineness of 585 therefore contains 585 g of pure gold per 1000 g of alloy, a gold product with a fineness of 750 means that 1000 g of alloy contains 750 g of pure gold, and 375 that 1000 g of alloy contains 375 g of pure gold.
White, pink and yellow gold
Gold is a precious metal found in yellow in nature. White or pink gold is obtained by means of alloying and processing techniques. To achieve the white colour, base gold is alloyed with other metals, such as nickel, silver, zinc, palladium, and platinum. Copper, for example, changes the golden colour into hues ranging from orange to pure copper of pink gold.
Platinum and rhodium baths
At Zlatarna Celje, we use Pt/Rh galvanic coating technology to achieve a white colour on the surface of the gold product. This creates a sub-micrometer coating that protects the surface of the jewellery from the release of nickel from the white gold alloy. At the same time, it also serves to protect the jewellery from external influences (moisture from the air, pH of the skin, etc.) in order to reduce the impact of factors that would significantly change the appearance of the jewellery. Galvanic coating also prevents direct contact of the base metal with the skin, which prevents the development of possible allergies.
The rhodium protection on jewellery, gold rings and bracelets exposed to mechanic contact with harder objects are more susceptible to wear of the Pt/Rh coating. In these spots, yellow undertones of white gold can develop in time.
The Pt/Rh coating can be restored by our Zlatarna Celje repair service.
Wearing jewelry worsens galvanic deposition and requires regular refreshing, especially in people prone to allergies.
Material wear
Since gold is a quite soft metal, minor scratches can appear on exposed parts of golden jewellery after coming into contact with harder objects. Jewellery can also become damaged if we wear several pieces at the same time (more rings with different stones on the same finger or more pendants on a necklace).
The manufacturing method cannot prevent any wear that occurs during everyday wear. Rings, especially wedding rings that we never take off and that most often come into contact with hard objects, are most exposed to this phenomenon. But wear tells the story of a lifetime, giving a personal touch to our jewellery.
The only way to protect the jewellery is to not wear it while performing tasks during which it would be more exposed to wear.
Colouration (darkening) of gold
In addition to gold, gold alloy also contains silver and copper that react with numerous sulphur compounds, thus forming sulphides. The thin layer of sulphides appears as colouration ranging from intensive yellow to red and brownish or, at a certain thickness, even black. Gold alloys with a fineness of 585 are usually colouration-resistant, unless they are exposed to larger quantities of hydrogen sulfide.
Contact with sulphur is also affected by other factors such as:
- the pH factor of the person wearing the jewellery,
- some medication consumed by the person wearing the jewellery,
- exposure to household chemicals,
- improper storage (in boxes with higher sulphur content),
- storage together with medications or some creams,
- heat and sweating (tropical conditions),
- certain creams, colours and hair shampoos, etc. especially those containing selenium,
- dietary habits (strong spices, chilli, onion and garlic, which can be excreted through skin, further accelerating the discolouration of gold),
- consumption of food supplements, especially those containing selenium.
Stones
The stones used to manufacture jewellery can be classified into three main groups:
– precious stones (diamonds, sapphires, rubies, emeralds),
– decorative stones or semi-precious stones (aquamarine, topaz, amethyst, citrine, beryl, tourmaline, tanzanite, morganite etc.),
– synthetic or artificial stones (made in laboratories, such as synthetic cubic zirconia - CZ).
Diamonds
Diamonds are the hardest natural minerals, with a hardness of 10 on the Mohs scale. The difference between a diamond and a brilliant is that diamonds are minerals, while a brilliant is the name of a particular round cut. The name “brilliant” is only used for round diamonds cut into 58 surfaces. The defining characteristics of each diamond, known as the 4Cs, are used to determine the estimate and value of every diamond:
1. Colour
Most diamonds used in goldsmithing are nearly colourless, with a yellow or brown tinge. Their colour is marked with letters ranging from D (colourless stones) to Z (slightly yellowish or brownish).
February Clarity
Clarity in cut stones is marked using the following abbreviations:
- FL: flawless stones without inclusions and surface features,
- IF: internally flawless stones which may only have surface features,
- VVS: stones with very very slight inclusions,
- VS: stones with very slight inclusions,
- SI: stones with slight inclusions,
- I or P: inclusions which may be visible to the naked eye.
3. Cut
Diamonds are cut into various shapes: rounds, navettes, squares, hearts, tears, ovals. The most common shape is a round brilliant cut.
4. Carat weight
Carats are the unit of measurement used for weighing carats, whereby 1 ct equals 0.2 g.
A detailed 4C scale can be found on our website www.zlatarnacelje.com.
Coloured diamonds
The variety of available colours opens up new horizons in terms of the creativity of our goldsmiths. Colour-treated diamonds are natural diamonds processed with electronic vapour and high temperatures. Different strength and time of exposure to the vapour and temperature account for different colours and shapes of diamonds.
When you know what you have
In Zlatarna Celje, we certify diamonds of up to 0.5 ct using globally recognised 4C criteria which define the main characteristics influencing the value of a diamond.
For diamonds of over 0.5 ct, a more complete certificate also provides additional properties influencing the value of a diamond.
It is good to know
Even though diamonds are hard minerals, they are not indestructible and may chip off when coming into contact with the edge of another hard object.
When exposed to ultraviolet (UV) light, many diamonds emit light and shine (due to the interaction of UV energy and the atoms in the diamond). In most natural diamonds, the fluorescence is more pronounced when exposed to long-wavelength UV rays or under strong sunlight compared to shorter-wavelength UV rays; some natural diamonds are known to be inert because they do not show fluorescence.
Diamonds bind fat well. This means that they look cloudy when dirty, which diminishes their shine which can be easily restored using lukewarm soapy water and a soft brush.
Sapphire
Sapphires are most commonly blue, but can also be found in yellow or pink. The most common cause for the difference in colour are admixtures of foreign ions such as iron and vanadium ions. In terms of hardness, sapphires come right after diamonds, reaching the value of 9 on Mohs scale.
Ruby
The magnificent red rubies are extremely rare and are, as such, one of the most valuable precious stones. In terms of hardness, these minerals also come right after diamonds, reaching the value of 9 on Mohs scale.
Emerald
The most precious emeralds are dark green, while extremely rare crystals are transparent. Emeralds almost always contain inclusions or veins, proving that they are natural stones, since those inclusions are precisely what sets them apart from imitations. Emeralds are very fragile because there are many internal stresses in them, which is reflected in their high sensitivity to compressive stress. The most desired colour is intense green, which is why those emeralds, even with inclusions, are more expensive than pale green or pure stones. The hardness of emeralds reach the score of 7.5 on the Mohs scale.
Decorative or semi-precious stones used in collections of Zlatarna Celje are aquamarine, amethyst, citrine, smoky quartz, hematite, calcedony, morganite, opal, onyx, spinel and topaz.
It is good to know
Regardless of whether we are talking about precious stones or gemstones, the thing we notice first is their colour, which is extremely important for defining the stone itself and its properties. In terms of natural stones, it is hard to find two stones of exactly the same shade, which is why any discrepancies in colour are not mistakes caused by the manufacturer and are therefore also not the basis for a complaint.
Pearls
Pearls are the only jewels growing in living organisms, i.e. in some types of marine, lake and river molluscs. Due to their compact crystal structure, they are extremely durable, but also soft. A flawless pearl is a rare treasure, which is why every jewel with a certain degree of imperfection is also more original. The only fatal flaws are cracks that impact their durability, while other characteristics only impact their appearance and quality. Since no two pearls are the same, a pearl that is lost or damaged is hard to replace with another pearl of the same shade.
Tips for handling pearls:
- Prevent the pearls from coming into contact with chemicals such as vinegar, chlorine, ammonia, bleaches, ink, hairsprays, perfumes and cosmetic products.
- Avoid storing pearls in extremely dry spaces. Pearls like humid environment, which is why very dry air can cause them to crack.
- Occasionally, pearls must be restrung. It is recommended to restring them no later than two years after purchase (depending on how often you wear them).
Synthetic cubic zirconia – CZ
Synthetic stones are artificial materials with mostly the same chemical composition, crystal structure and optical and physical properties as the natural material. They have been invented as an alternative to diamonds and are available in nearly any colour.
Lencia silver jewellery
Lencia is a popular brand of the Zlatna Celje European design, which combines the use of modern technology with careful handwork to ensure the flawlessness of the jewellery. The jewellery is made of 925/000 sterling silver, and is additionally protected against chemical influences from the air and skin with a rhodium (Rh) coating.
Silver
The chemical symbol for silver is Ag and is derived from the Latin word Argentum.
Silver is considered one of the precious metals and is a uniform metal with a shining white metallic sheen that can be easily polished. Silver is highly malleable and easy to work with.
Rhodium (Rh) baths
We use the Rh-baths to protect silver jewellery.
The baths apply a thin coating on the surface of the jewellery to protect the metal from outside influences or prevent the contact between the Ag alloy and factors that could cause it to change (moisture from the air, pH of the skin etc.).
Jewellery, especially rings and bracelets, which are exposed to mechanical contact with rigid objects, are more susceptible to wear of the Rh-protection and where the coating wears off over time, the silver is thus exposed to environmental influences and can oxidise, tarnish.
The Rh coating can be restored by our Zlatarna Celje repair department.
Gold plating
We use several types of gold when creating Lencia jewellery, such as classic yellow and rose gold plating (with more copper and other additives added). All types of gold plating are also surface treatments of jewellery, namely the application of an additional material to the base material of silver. Therefore, it is important to keep in mind that gold plating will wear out or peel off over time. Since these are sub-micrometre coatings, colour fading may also occur. This type of wear is not the fault of the manufacturer and cannot be the subject of a complaint.
Stones
The stones used to manufacture the Lencia jewellery can be classified into two groups:
- natural stones, such as: freshwater pearl, smoky quartz, onyx, coral, chalcedony, jasper;
- synthetic or artificial stones (made in laboratories, such as synthetic cubic zirconia - CZ or glass pearl or crystal).
Certain deviations in colour shades may occur with natural stones precisely because of their natural colour. For example, the colour of the embedded stone in the ring may differ slightly from that of the stone in the pendant. Natural stone is not artificially coloured and thus one is not the same as another. Such deviations in colour are not a fault of the manufacturer, and thus differences between individual pieces of jewellery are not subject to complaints.
Crystals are also incorporated into Lencia jewellery, which are sensitive to impacts and other mechanical influences, much like glass and crystal glass. Therefore, such jewellery should be stored and kept separate from hard objects that could cause scratches or dislodge exposed stone tips before physical handling. This type of damage is not the fault of the manufacturer and thus cannot be the subject of a complaint.
Fashionable glass beads, also known as “artificial beads”, where the base of the bead is coated with pearl-like artificial material and lacquer, can crack and begin to crumble when subjected to mechanical damage (rubbing, scratching) and fall off the base.
Textile bands
The textile bracelet must not come into contact with water as this may damage the fabric. The wear of the textile band (layering of the fabric, fading of the colour, creasing, stretching along the length, etc.) is the result of wearing the bracelet and cannot be the subject of a complaint, even within the warranty period of 6 months. Textile bands are not replaceable.
Leather
Water, sweat, cosmetics, and harsh cleaners cause the natural shine of the leather parts to be lost, which can cause cracks, discolouration, and other damage to the skin. Such wear occurs due to wearing the bracelet and cannot be the subject of a complaint, even during the 6-month guarantee period.
Tips on keeping your jewellery intact
Oxidation appears in moist or wet conditions, especially if jewellery is exposed to heat or air.
Jewellery, in particular rings, which are decorative in nature, are not intended to be subjected to excessive mechanical, chemical or thermal stresses. Rings and all other pieces of jewellery are not considered as suitable for wear or use which is likely to cause damage or significantly shorten their life, as in the following cases:
- wearing during heavy physical tasks (lifting, physical work, sports activities, gym, cycling),
- household work (cleaning, washing, cooking) where the ring can suffer impacts or be damaged,
- work with tools or machinery,
- contact with aggressive chemicals, detergents cleaning agents,
- contact with make-up, hairspray, creams and perfumes,
- bathing in pools or swimming in the sea where the presence of salts and chlorine, which may cause discolouration of jewellery, affects the appearance of the surface or stone,
- wearing jewellery in sulphurous, thermal waters, because the jewellery may tarnish,
- sleeping with jewellery, as the inserts may become stuck or bend.
For a long life and flawless appearance of jewellery (especially rings), we recommend:
- that you take it off before the above-mentioned activities, but it is also recommended to remove the ring from time to time for reasons of hygiene or skin care,
- that you keep it in a dry, soft case, separate from other jewellery,
- that you occasionally clean it with a dry, soft cloth or take it to a professional cleaner.
Here are a few more simple tips to follow
The best rule to follow is to put on your jewellery last in the morning and take it off first in the evening.
Keep it in a box, with each piece in a separate bag or soft cloth to prevent scratches.
Take photographs of all your jewellery to document your property in the event of theft or loss.
Keep the certificates and invoices for your jewellery; this is the only way for you to quickly prove its authenticity. You will also need a certificate and/or invoice if you want to hand it over to the repair service.
Maintain the sheen, luster and prestigious appearance of your jewellery by gently cleaning it using a moist cloth.
We recommend that you bring your jewellery to Zlatarna Celje for examination at least once a year and benefit from our payable jewellery repair or cleaning services.
The warranty for gold jewellery covers all factory (material or manufacturing) errors discovered within 12 months of the date of purchase.
The warranty for silver jewellery covers all factory (material or manufacturing) errors discovered within 6 months of the date of purchase.
Our workshop will remedy the errors within the warranty period by repairing the article; failing that, your article will be exchanged or replaced by the same new article. The error remedy method is at the discretion of Zlatarna Celje.
The warranty is valid upon presentation of the original or gift invoice, certificate and/or purchase receipt.
The warranty does not apply to mechanical damage caused by:
- improper handling or wearing,
- negligence,
- attempts to repair your jewellery yourself.
Any repairs due to mechanical damage or after the warranty period are available in the official repair service of Zlatarna Celje and are subject to the valid price list. We repair all products by Zlatarna Celje, d. o. o., upon presentation of the invoice, certificate and/or purchase receipt.
The warranty does not exclude the rights of the consumer, which arise from the seller's liability for defects on goods.
Zlatarna Celje, d. o. o., Kersnikova 19, 3000 Celje, Slovenia