Fracture filling, sometimes known as “clarity enhancement,” is a process whereby any surface-reaching fissure in a gemstone can be filled in order to enhance the gemstone’s beauty, durability, or both.
It is important to note that gemstones have been treated in a variety of ways for hundreds and in some cases, thousands of years. Emeralds were oiled to enhance their beauty as long ago as the days of Cleopatra, if not before! Enhancing techniques in and of themselves are not necessarily detrimental or unethical. Failure to disclose their presence, however, is another matter.
Oiling of emeralds has continued to this day. However, modern technology has allowed producers to go further in the enhancement of emeralds as well as many other gemstones. Various substances such as polymers (colorless or dyed) are now being applied to a variety of materials. Treatments in many cases benefit the consumer, as in the case of polymers that strengthen emeralds while enhancing their beauty. One such filling material, known as the Gematrat® treatment, is so stable that it allows treated emeralds to be ultrasonically cleaned. Oiled emeralds cannot be cleaned ultrasonically because the cleaning action damages or removes the oil and negatively affects the appearance of the emerald. Stable or not, polymer or oil, dyed or not dyed, any and all of these treatments must be disclosed to consumers by the seller.
Fracture-filling in diamonds is a process invented during the 1980’s, and involves the infusion under high heat and pressure of a compound that fills surface reaching fissures, thereby making them less visible. An experienced gemologist will detect the filler in the form of bright blue and/or orange flashes visible under magnification under proper lighting, viewed at a particular angle to the filled fissure. Various studies of the filler material seem to indicate that it may change color with age. Also, the filler will be melted or burned by the torch heat required to 3affect certain repairs such as prong re-tipping.
On the positive side, fracture filling dramatically improves the appearance of otherwise unattractive diamonds, and allows consumers with a limited budget to purchase a great deal more “look” than they might otherwise be able to afford.
Disclosure of compounds used to fracture-fill diamonds and other gemstones should include information about the care required to ensure the maximum life span of the filler material.
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