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World’s Leader for Colored Stones

Thailand is one of the world’s largest centers for colored stones, particularly rubies, sapphires and emeralds, with innovative techniques for enhancing their quality and appearance plus craftsmen skilled at polishing and setting these beautiful stones into stunning jewelry. Thailand is also renowned for cutting and polishing diamonds, producing high quality products of colored stones and diamonds to be among the country’s top exports.

Artistic Flair & Innovation

Imaginative designs flow effortlessly from the drawing boards of Thailand’s jewelry craftsmen. Their artistic flair, style of setting and combination of gems, especially when working with gold and silver, result in breathtaking creations that are in high demand internationally. Not surprisingly, the world’s jewelry traders view Thailand as an incomparable source of innovative designs.

Top Quality in Cutting & Setting

Meeting world standards of quality in cutting and setting gems and jewelry is the major reason for Thailand’s success, aided by a highly skilled workforce with outstanding abilities in setting and design. Such skills ensure consistency in quality and reliability in production of each piece of jewelry enhanced by assured after-sales service.

Trendy Fashionable Silver Jewelry

Gold and silver are important elements in the country’s growing exports of high quality gems and jewelry products. However, a long tradition of Thai artisans working in high purity silver, with intricate designs and superb embellishments, is now generating growing international interest in the country’s silver creations as trendy White Wave fashion items.

Traditional Wisdom & Modern Technology

Thailand has developed a special heat treatment technique to enhance the quality of colored stones, increasing their brightness and clarity. The industry is well supported by the Gem and Jewelry Institute of Thailand, an outstanding analytical laboratory that is ranked one of the top seven in the world, also recognized by CIBJO (The World Jewellery Confederation). Its experienced gemologists are able to analyze, grade and authenticate gemstones, trace country of origin and provide internationally recognized certification for exporters.

A Reputation for Skilled Artisans

A well-trained workforce provides extraordinary skills in cutting, setting, design and craftsmanship. All at very competitive labor rates, has enabled Thailand to serve many different markets with a variety of products ranging from commercial to top quality.

How to Buy Gems and Jewelry

1. First, it is essential to have the basic knowledge about the 4Cs characteristics, Color - Clarity - Cut and Carat weight of the gemstones/diamonds you are selecting.

2. The jewellers must provide another C “Confidence”. Knowledgeable and generous jewellers can help and advise customers to select the right gems and jewelry that suit their taste and budget.

3. There are 2 categories of gemstones: precious stones and semi - precious stones. Precious stones are diamond, ruby, sapphire, yellow sapphire, emerald, etc. Semi - precious stones are tourmaline, peridot, tanzanite, garnet, opal, spinel, zircon, aquamarine, pearl, etc.

4. The commercial value, hardness and durability of semi - precious stones are normally less than precious stones.

5. Two gemstones/diamonds of equal carat weight can have very different values depending on their color - clarity and cut. Therefore, remember to inspect their quality by using a 10X magnifying loupe under the jeweller’s guidance.

6. Be careful with synthetic and imitation gemstones/diamonds. For ruby and sapphire, be aware of mistaking and paying the price of a blue gemstone for a sapphire and a red gemstone for a ruby.

7. Prices of gold/silver/platinum jewelry are subject to the weight and percertage of the material, craftsmanship and designs.

Shopping Advice

1. Never let a tout or a new found friend take you shopping. Stores give commissions to these people and that cost is reflected on the price you pay.

2. Choose a shop carefully. Make sure it is a specialist in the field and not simply a general store. The JFC and the BWC member shops are recommended for your shopping.

3. Shop around to compare prices, though be sure to make comparisons between similar items - this is especially important with gems and jewelry.

4. Assess the sales assistants. Do they appear knowledgeable? Are they willing to discuss an item’s bad as well as good point?

5. Take your time, never let a shop assistant pressure you into a purchase.

6. Ask for a receipt with warranty/certificate for goods bought and check that it is correct before leaving the shop.

7. Finally, your best guide is what you like. Don’t, for example, buy gems or jewelry for the purpose of re-sale or investment. They may have such appreciation potential, but there are no guarantees. Shop for pleasure not for profit.

Your guide to diamond quality and value

The 4Cs of diamonds are the criteria jewellers use when grading diamonds, and they are the one you will need to understand to buy the right diamond for yourself.

Cut: A good cut diamond with its proper proportions brings out more brilliance and more sparkles. Diamonds can be cut in various shapes (e.g. round, squre, heart, etc) the brilliant or round is the most classic and popular.

Color: Most diamonds vary in shades from colorless to yellow, which are ranged from D-Z; D E F = Colorless / G H I =Near Colorless / K L M = Faint yellow / N O P Q R =Very light yellow / S-Z=Light yellow. Colorless is extremely rare. Other colors occur also in diamonds such as yellow, orange, pink, blue, etc. The most intense of these shades are determined as “Fancy” colors.

Clarity: All diamonds have identifiable characteristics, but most are invisible to the naked eye. Under a 10X magnifying loupe, diamond clarity is graded into 6 categories. FL = Flawless / IF = Internally Flawless/ VVS1 VVS2 = Very Very Small Inclusions / VS1 VS2 = Very Small Inclusions / SI1 SI2 = Small Inclusions / I1 I2 I3 = Inclusions

Carat weight: The weight or size of diamonds is measured is carats. A carat is 0.2 grams and there are 100 points (or 200 milligrams) per carat.

Be aware of numerous imitations of diamonds: cubic zirconia, synthetic moissianite, synthetic rutile, strontium titanate, colorless topaz, colorless sapphire, and many others. Scratching glass is a useless test as many imitations also scratch glass. Consult a professional, independent retail jeweler to insure you are getting the real thing. If you are making a large investment in a diamond, make sure that you are getting a diamond grading report from a reputable gemological laboratory.

Ruby & sapphire Guide

The quality and value of a ruby / sapphire depend on a combination of the following criteria:

Carat Weight: Weight of a ruby / sapphire is measured in carats.1 carats = 0.2 grams. The heavier and the larger the ruby / sapphire, usually the more rare it is.

Cut: Cut refers to the accuracy of the angles, proportions, symmetry and polish of the ruby /sapphire. It greatly affects how light travels within the ruby /sapphire, and how it exits in the form of brilliance. To optimize the natural rough, rubies /sapphires are cut into a wide variety of shapes such as those illustrated below.

Color: Color is a matter of personal preference. Rubies vary in color depending mainly upon their chromium and iron content, whereas sapphires vary in color depending mainly upon their titanium and iron content, Therefore ruby /sapphire from different countries* and mines have different predominant color.

Rubies: Primarily red, range from brownish and purplish shades to orangish and pinkish ones.

Sapphires: Primarily blue, range from dark and purplish shades to greenish and yellowish ones. But, a natural color of ruby / sapphire will always have a greater value than a equivalent color obtained by heating or other processes.

Clarity: The clarity of a ruby / sapphire is determined by the number, size and location of inclusions which are natural materials present in the stone. They reflect its fascinating geological aspects, internally and externally too, there may be the presence of fissures, fracture and cavities which affect clarity.

Transparency: Transparency refers to the ability of a ruby / sapphire to transmit light. It is affected by the quantity or absence of opacity and brilliance present in the stone.

Gemstone Modification

Besides Cutting and polishing, rubies / sapphires are commonly modified to improve their color and clarity. It is required that customers be informed about such modifications. Ask for a written confirmation. The correct nomenclature of modified gemstones can be found in the CIBJO Gemstone Book.


Value of a Gemstone

Moreover, the value of a gemstone is also defined by the combination of relative beauty, rarity and durability. Synthetic and imitation stones can be produced in industrial plants in any quantity and are therefore not rare and not considered precious. As a result, they cost much less than their natural counterparts of equal characteristics.


Emerald Guide

Emerald is the bluish green to green variety of beryl family of minerals. Color is the biggest factor in establishing the value and quality in natural emeralds. Emeralds come in a range of green shades, from light to dark with tints of other colors ranging from yellow to blue. The most desirable emerald colors are bluish green to pure green with vivid color saturation and the tone that is not too light or too dark. The color is evenly distributed. If the hue is too yellowish or too bluish, the stone is of a different variety of beryl.

Emeralds by nature contain inclusions that are visible to the unaided eye. The trade generally accepts eye-visible inclusions but when the inclusions have a negative effect on transparency and clarity, or compromise the durability of a stone, they can lessen the value. Eye-clean emeralds are especially valuable because they’re so rare. However, any emerald without inclusion or appears flawless could be suspected to be synthetic or simulant.

Pearl Guide

Knowing pearl types is the first step of evaluating pearls. Each type of pearls has its own characteristics and valued standards. Basically, all pearls can be listed in two categories: Freshwater Pearls and Saltwater Pearls. The three most common saltwater pearls are Akoya pearl, Southsea pearl and Black Southsea pearl/ Tahitian pearl. Among different types of pearls, saltwater pearls are more valuable than freshwater pearls. It can also be divided into Natural pearls and Cultured pearls. Natural pearls cost more than cultured pearls. The high value of natural pearls does not mean they are better quality than cultured ones. That is just because they are rare.

Luster might be the most important factor of all. Luster is the amount of light a pearl reflects. Pearls with high luster have sharp bright reflections on the surface. Different pearl types have different standards for luster. Among all types of salt water pearl, Akoya pearl often shows high luster.

The qualities that determine a natural or cultured pearl’s value are luster, nacre quality, size, shape, color, and surface quality.

Luster and nacre quality are closely related. if the pearl has a dull, chalky appearance, you can assume that the nacre could be thin. This affects the luster as well as the durability of the pearl.

If everything else is equal, the larger the pearl, the more valuable it is. As the size reach the 8 - 9 mm or above, pearl prices tend to increase much higher. Different varieties of pearl come in different sizes. Southsea cultured pearls are the largest.

Pearl experts generally divide pearl shape into four main categories: Round-Spherical, Off Round, Semi-Baroque and Baroque. Perfectly spherical pearls and symmetrical drops are the most valued. The perfection of a round pearl is considered most suited to showing off a pearl’s innate beauty. However, other shapes can be quite unique and can be created into interesting jewelry pieces.

Pearls come in a wide variety of colors, ranging from white to black. The color of pearls results from a combination of body color, overtone and iridescence. The main color, or body color, is often modified by overtones, which are typically pink, green, purple, or blue. The most familiar body color are white and cream. Black, gray, and silver are also common, but the color range extends to every hue. As color is personal preferences, most people choose the color they feel compliment to their natural skin tones.

A pearl with a clean surface will reflect light more evenly and is therefore more highly valued than a pearl with a blemished surface. Even though a pearl Is considered more valuable when the surface blemishes are minimal, we should positively consider them more than negative when evaluating pearls. Surface imperfections are part of a pearl’s natural texture and proof of the pearl’s genuineness.

Gems & Jewelry Care

• It’s a good idea to take your rings off when doing rough work. Even though diamonds are durable, they can be chipped by a hard blow. Perspiration and dirt can cause your jewelry to become dull.

• When you are not wearing your jewelry, put it in a fabriclined jewelry case with dividers.

• Don’t expose your jewelry to saltwater or harsh chemicals,like chlorine bleach.

• Don’t wear your sterling silver jewelry in chlorinated water.

• The use of hairspray, cosmetics, hand lotions and perfumes can cause jewelry to become dull. Put your jewelry on after you have used any of these to prolong their luster.

• Store your silver in a cool, dry place, preferably in a tarnish preventative bag or wrapped in a soft piece of felt or cloth.

• It is a good idea to bring your pearls to your jeweller at least once a year to have them restrung. Normal wear tends to weaken and stretch the threads on which pearls are strung.

• When you have your pearls restrung. make sure they are knotted between each pearl. This will prevent the loss of pearls if the string should break.

• Replace broken or scratched watch crystals promptly, even the smallest crack can let in dust or moisture that can threaten its accuracy.

• Pearls, coral and porous stones such as opal, turquoise and malachite should be kept away from oils, chemicals and dirty water to avoid discoloration. Wipe them gently with a soft, damp cloth.

• Ultrasonic cleaners should not be used with stones subject to internal stress such as tanzanite, opal, emerald, organic gems (pearl, coral and amber), turquoise, lapis, malachite and any stones containing major inclusions.

• Opal, pearls, coral, amber and turquoise are heat sensitive (both to extreme and sudden changes in temperature). Do not leave them in hot sunlight, near radiators, or in hot cars.