Product Name: Natural Red Ruby Product Type: Genuine Gemstone Weight: 0.75 CTSShape: Oval Cut Size: 7.5 mm X 5 mm Depth: 4 mmColor: Red Clarity: Transparent Luster: Good Hardness: 9 Treatment: Treated Origin: Africa
Why Some Treatments Are More Accepted Than Others
The fact is most gemstones used in jewelry have been treated to improve their appearance. Treated gemstones can be a good choice, because they should be more affordable than untreated stones that achieve their quality naturally. Do you know what the common treatments are? Some last forever, some don't.
Many gemstones are treated with various methods to improve color and clarity. Some of these methods are widely accepted in the trade today, while other methods are not. The accepted trade methods are the ones that will change the color of the gemstone permanently.
Some treatments bring out the stone's inherent qualities. Emeralds, for example, are routinely oiled to bring out their color. Such treatments do not camouflage flaws or harm the stone in any way. The jewelry retailer need not specifically mention treatments that are regarded as the usual way of dealing with that kind of gem.
Other treatments are done to stones of lower quality to make them appear more attractive. Although a trained gemologist can see, under a microscope, that the stone has been treated, the purchaser cannot. If the seller does not disclose such treatments, a customer would believe the gem to be of higher quality than it is and might be led to pay a higher price.
All ethical gem dealers will fully disclose gem treatments. But in our view it is also important to provide detailed information to the buyer so that he knows exactly what he is buying. Keep in mind that most colored gemstones are treated, and this is a perfectly legitimate practice as long as all facts are disclosed to the buyer. If you know the facts, then you can feel safe about buying a gemstone that you will enjoy for many years to come.
Procedures that Enhance Gemstone Appearance
Colored gemstones nearly always undergo some sort of appearance-enhancing treatment before they are used in jewelry. Some treatments are permanent, but others are not. Get the facts about gemstones enhancements before you shop for jewelry.
Not all treatments are regarded as equal. Consider these factors when determining the acceptability of a gemstone:
1) Is the treatment permanent?
2) Has the treatment added foreign material to the gemstone?
3) Has the internal character of the gemstone been changed by the treatment?
4) Does the treatment decrease durability?
5) Does the treated gem compete with a natural gem?
6) How available are attractive untreated gems of the same type?
PERMANENCE: Irradiated yellow sapphires may fade within minutes of being treated so they’re not accepted. However, the heat treatment of sapphires is accepted because a stable color is usually produced.
The color of irritated pearls is stable and does not rub off on your skin like dye of some dyed pearls. This is one reason irritated pearls are preferred over dyed pearls.
Laser drilling is more accepted diamond treatment than fracture filling because lasering produces permanent results. Fracture filling is subject to change if the filled diamonds come in contact with a jeweler’s torch or if they’re subjected to prolonged or multiple ultrasonic cleanings. Some fillings cloud or discolor when exposed to light for long periods.
ADDITIONS OF FOREIGN MATERIAL: Another reason why heating and irradiation may be preferred to other treatments is that no chemicals, oils, wax or synthetic substances are added to the stones, except when the stones are heated in borax. When the borax turns into glass and fills cracks or cavities, this is undesirable and can reduce the value of expensive rubies, for example.
INTERNAL CHANGE: Heat treatment done at 1600’C (2900’F) and above can melt inclusions, create tiny stress cracks, produce a hazy appearance and change the overall internal character of a gemstone. This is one reason why low-temperature heat treatment is preferred to high temperature heating.
DURABILITY: Treatments can have a negative effect on durability. According to Dr. Kurt Nassau (Gemstone Enhancement, page 43), “High temperature heat treatments may cause some materials to become more brittle and shows more wear.”
The GIA Gem Reference Guide notes on page 262 in the section on zircon, “Toughness: heat-treated stones-poor to fair; untreated stones-fair to good.”
According to Dr. Horst Krupp, a heat treater and physicist, high temperature can cause can cause rubies and sapphires to become brittle and abrade if they’re not properly cooled during the heat treatment process. This is another reason high temperature heating can have a negative impact on gem prices.
Burmese jade is sometimes soaked and bleached in chemicals to remove brown or yellow impurities. This weakens the jade. Occasionally treatment can improve durability. Most natural turquoise can crack or crumble. When it’s impregnated with a plastic material and it becomes more durable.
COMPETITION: Small Japanese pearls (akoya pearls) that have been darkened by irradiation and/or dyes are accepted by the trade because the treatments provide consumers with an option not available from natural-color akoya pearls.
Artificial colored South Sea pearls are not well accepted. In fact they’re banned in Tahiti because they compete with Tahiti’s naturally colored black pearls, and they confuse buyers.
There are strong objections to the new HPHT-treated diamonds because they compete with high-quality untreated diamonds and they complicate buying, selling and identification.
Most tanzanite is heat-treated to intensify the color and/or eliminate brown, gray or green. The low-temperature heat-treatment (600-700 degrees centigrade), which produces a stable color is well accepted and is used even on the finest stones. Tanzanite was unknown before the 1960’s so heat treated tanzanite has not competed with an existing market of untreated stones. Contrary to what is sometimes reported, there are attractive untreated tanzanites, but the percentage is negligible.
AVAILABILITY: Oiling emeralds is a well-accepted trade practice because emeralds typically have cracks and need to be fracture filled to improve their clarity. Therefore when buying expensive emeralds, assume they’ve been fracture-filled with oil or some other substance. Your main concern should be to what extent the treatment has affected the appearance. This information is now provided on many emeralds lad reports.
Unoiled rubies are readily available, so ruby oiling isn’t accepted though it’s often done when surface cracks are present.
Precautions to Take When Buying Expensive Gems
When you spend a few hundred dollars on a gem, the treatment status is normally not a major issue. In fact, you can just assume that the rubies, sapphires, aquamarines and tanzanite’s you see have been heat treated and the emeralds have been fracture filled. Enjoy wearing these gems and appreciate the fact that treatments allow you to buy more attractive stones at lower prices.
However, when you spend a few thousand dollars or more on a gemstone, the type and extent of the treatment is an important buying factor. Take these precautions:
1) Use caution when you shop on the web. The Federal Trade Commission has discovered a number of online jewelry retailers and auction sites that are not complying with disclosure requirements for colored gemstone treatments (among other things). Do not shop for price alone.
2) Deal with sellers who can explain treatments in frank simple language rather than with euphemisms and vague terms.
3) Deal with sellers who will tell you both the bad and good points about treatments.
4) Ask if and how stones gave been treated. The answer will give you insight into the seller’s ethics.
5) Have the salesperson include treatment information on the receipt. If the stone is untreated, have this written.
6) For expensive gems, get a report form a lab that automatically includes treatment on their documents.
If the retailer does not mention treatments, always ask whether the gem has been treated. (Read about the treatments common to the gems you are buying.) Treatments should be disclosed on the sales receipt and on the appraisal.
All treatments that are not accepted as part of the normal processing of a gem should always be specifically disclosed, both verbally and on the sales receipt.
The fact is most gemstones used in jewelry have been treated to improve their appearance. Treated gemstones can be a good choice, because they should be more affordable than untreated stones that achieve their quality naturally. Do you know what the common treatments are? Some last forever, some don't.
Many gemstones are treated with various methods to improve color and clarity. Some of these methods are widely accepted in the trade today, while other methods are not. The accepted trade methods are the ones that will change the color of the gemstone permanently.
Some treatments bring out the stone's inherent qualities. Emeralds, for example, are routinely oiled to bring out their color. Such treatments do not camouflage flaws or harm the stone in any way. The jewelry retailer need not specifically mention treatments that are regarded as the usual way of dealing with that kind of gem.
Other treatments are done to stones of lower quality to make them appear more attractive. Although a trained gemologist can see, under a microscope, that the stone has been treated, the purchaser cannot. If the seller does not disclose such treatments, a customer would believe the gem to be of higher quality than it is and might be led to pay a higher price.
All ethical gem dealers will fully disclose gem treatments. But in our view it is also important to provide detailed information to the buyer so that he knows exactly what he is buying. Keep in mind that most colored gemstones are treated, and this is a perfectly legitimate practice as long as all facts are disclosed to the buyer. If you know the facts, then you can feel safe about buying a gemstone that you will enjoy for many years to come.
Procedures that Enhance Gemstone Appearance
Colored gemstones nearly always undergo some sort of appearance-enhancing treatment before they are used in jewelry. Some treatments are permanent, but others are not. Get the facts about gemstones enhancements before you shop for jewelry.
Not all treatments are regarded as equal. Consider these factors when determining the acceptability of a gemstone:
1) Is the treatment permanent?
2) Has the treatment added foreign material to the gemstone?
3) Has the internal character of the gemstone been changed by the treatment?
4) Does the treatment decrease durability?
5) Does the treated gem compete with a natural gem?
6) How available are attractive untreated gems of the same type?
PERMANENCE: Irradiated yellow sapphires may fade within minutes of being treated so they’re not accepted. However, the heat treatment of sapphires is accepted because a stable color is usually produced.
The color of irritated pearls is stable and does not rub off on your skin like dye of some dyed pearls. This is one reason irritated pearls are preferred over dyed pearls.
Laser drilling is more accepted diamond treatment than fracture filling because lasering produces permanent results. Fracture filling is subject to change if the filled diamonds come in contact with a jeweler’s torch or if they’re subjected to prolonged or multiple ultrasonic cleanings. Some fillings cloud or discolor when exposed to light for long periods.
ADDITIONS OF FOREIGN MATERIAL: Another reason why heating and irradiation may be preferred to other treatments is that no chemicals, oils, wax or synthetic substances are added to the stones, except when the stones are heated in borax. When the borax turns into glass and fills cracks or cavities, this is undesirable and can reduce the value of expensive rubies, for example.
INTERNAL CHANGE: Heat treatment done at 1600’C (2900’F) and above can melt inclusions, create tiny stress cracks, produce a hazy appearance and change the overall internal character of a gemstone. This is one reason why low-temperature heat treatment is preferred to high temperature heating.
DURABILITY: Treatments can have a negative effect on durability. According to Dr. Kurt Nassau (Gemstone Enhancement, page 43), “High temperature heat treatments may cause some materials to become more brittle and shows more wear.”
The GIA Gem Reference Guide notes on page 262 in the section on zircon, “Toughness: heat-treated stones-poor to fair; untreated stones-fair to good.”
According to Dr. Horst Krupp, a heat treater and physicist, high temperature can cause can cause rubies and sapphires to become brittle and abrade if they’re not properly cooled during the heat treatment process. This is another reason high temperature heating can have a negative impact on gem prices.
Burmese jade is sometimes soaked and bleached in chemicals to remove brown or yellow impurities. This weakens the jade. Occasionally treatment can improve durability. Most natural turquoise can crack or crumble. When it’s impregnated with a plastic material and it becomes more durable.
COMPETITION: Small Japanese pearls (akoya pearls) that have been darkened by irradiation and/or dyes are accepted by the trade because the treatments provide consumers with an option not available from natural-color akoya pearls.
Artificial colored South Sea pearls are not well accepted. In fact they’re banned in Tahiti because they compete with Tahiti’s naturally colored black pearls, and they confuse buyers.
There are strong objections to the new HPHT-treated diamonds because they compete with high-quality untreated diamonds and they complicate buying, selling and identification.
Most tanzanite is heat-treated to intensify the color and/or eliminate brown, gray or green. The low-temperature heat-treatment (600-700 degrees centigrade), which produces a stable color is well accepted and is used even on the finest stones. Tanzanite was unknown before the 1960’s so heat treated tanzanite has not competed with an existing market of untreated stones. Contrary to what is sometimes reported, there are attractive untreated tanzanites, but the percentage is negligible.
AVAILABILITY: Oiling emeralds is a well-accepted trade practice because emeralds typically have cracks and need to be fracture filled to improve their clarity. Therefore when buying expensive emeralds, assume they’ve been fracture-filled with oil or some other substance. Your main concern should be to what extent the treatment has affected the appearance. This information is now provided on many emeralds lad reports.
Unoiled rubies are readily available, so ruby oiling isn’t accepted though it’s often done when surface cracks are present.
Precautions to Take When Buying Expensive Gems
When you spend a few hundred dollars on a gem, the treatment status is normally not a major issue. In fact, you can just assume that the rubies, sapphires, aquamarines and tanzanite’s you see have been heat treated and the emeralds have been fracture filled. Enjoy wearing these gems and appreciate the fact that treatments allow you to buy more attractive stones at lower prices.
However, when you spend a few thousand dollars or more on a gemstone, the type and extent of the treatment is an important buying factor. Take these precautions:
1) Use caution when you shop on the web. The Federal Trade Commission has discovered a number of online jewelry retailers and auction sites that are not complying with disclosure requirements for colored gemstone treatments (among other things). Do not shop for price alone.
2) Deal with sellers who can explain treatments in frank simple language rather than with euphemisms and vague terms.
3) Deal with sellers who will tell you both the bad and good points about treatments.
4) Ask if and how stones gave been treated. The answer will give you insight into the seller’s ethics.
5) Have the salesperson include treatment information on the receipt. If the stone is untreated, have this written.
6) For expensive gems, get a report form a lab that automatically includes treatment on their documents.
If the retailer does not mention treatments, always ask whether the gem has been treated. (Read about the treatments common to the gems you are buying.) Treatments should be disclosed on the sales receipt and on the appraisal.
All treatments that are not accepted as part of the normal processing of a gem should always be specifically disclosed, both verbally and on the sales receipt.
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