Treatments / Enhancements

Almost all gemstones are treated to help them show the full beauty of their crystals. 98% of all emeralds are enhanced with a liquid or resin after cutting. Similar practices are carried out on diamonds (ie. laser drilling, etc.), sapphires (ie. glass filling) and most other gemstones.

Emeralds are frequently treated with oil or other "fillers". On a microscopic level, these substances will fill the fissures to improve the clarity of the Emerald. Visual look will slightly improve but it cannot make a dramatic change in the appearance. For example, it cannot make a heavily included Emerald appear to have very slight inclusions.

Emeralds are occasionally colour-enhanced by introducing dye into surface reaching fissures trying to deepen the green colour of less valuable lighter Emeralds. There has been much controversy over enhancements or treatments. Any process which goes beyond simple "enhancement" of the refractive index of the stone is something that only a customer should discuss with the seller. Even colour treatment, is usually minor in thin fissures, but be vigilant on specimens with gross surface-reaching fissures. This treatment can be detected by observing the Emerald under magnification.

We provide disclosure of any treatment. The emeralds we offer at muzo.net.au range from untreated emeralds to treatments with cedar oil or permasafe. These DO NOT dye or colour enhances the emeralds. These treatments are accepted by the Gemmological Institute of America (GIA).

Common practice is that even Emeralds that have very few or no surface-reaching fissures are typically included in the "lot" and oil is applied to them along with those that do have surface-reaching fissures. Therefore, if the emerald has no fissure to fill, then this treatment has small significance.

The following is a brief synopsis of the most common emerald Enhancements / Treatments used. Followed by their Enhancement Codes.

Cedar Wood Oil

Natural colourless Cedar Wood oil has been used in emeralds since the 1960's. Oil distilled of the leaves of the "Junipers Virginian". It is an liquidate colourless dissolved in alcohol.
Specific Gravity: 0.94 - 0.98
Refractive index: (20°C) 1.50 and 1.52

This has been the conventional way to treat emeralds and was the first worldwide accepted. Cedar wood oil is not permanent and requires special care, but does not affect much the value of the gem. The emerald might need to be re-oiled if heated too much, but lightly enhanced ones rarely change. Code: E-Colorless-Oiled

PERMA SAFE

The Permasafe Lab in Bogota has recently provided an improved version of permanent enhancement. PermaSafe is an epoxy resin, similar in some ways to the secret material used in the Arthur Groom-Gematrat enhancement (Professional Jeweler,April 1998, p. 50). Both treatments are durable and can withstand ultrasonic cleaners and the heat of a cutting wheel.  PermaSafe reportedly can be removed from the emerald and fluoresces a pale blue in long wave ultraviolet light for easy identification.

PermaSafe is touted to be transparent and closer to emerald's refractive index, thereby concealing fissures more effectively. It is also less viscous and can permeate emeralds with a minimum of heat and pressure.

The purpose here was to improve the durability of emerald enhancements to make a way toward re-establishing market confidence. The majority of our gemstones are treated with PermaSafe from CGIE (Centro Gemologico para Investigacion de la Esmeralda - Gemmological Centre for Emerald Investigation)

Permasafe does not colour treat stones. Like AG, the Permasafe group is one of the most advanced in attempting to fully clean out merchandise before enhancing. Code: E-Colorless-Resined

AG GEMATRAT

The Arthur Groom lab of New York created this substance which is an improve option over opticon. According to Mr. Groom his enhancement will not turn yellow. The benefit as well is that it will not leak out of the stone and he claims that you can steam clean or ultrasonic this emerald without ever losing the enhancement. Gematrat does not colour stones. Gematrat has a refractive index that is very close to that of true emerald. Code: E-Colourless-Resined

ExCel

Created by the same Arthur Groom laboratories. ExCel is an improvement on their previous gematrat. ExCel's latest version as of May/03 is nicknamed "1.52" in an effort to show how its refractive index is similar to that of cedar oil and now lower than his previous Gematrat. Code: E-Colourless-Resined

PALM RESIN 828 & 6010

"Palma" was introduced after many of the Cedar Wood stones lost their oil during long distance trasports. They decided to make a special plastic like Opticon which would fill the inclusions and stay in the stone. Unfortunately, Palma turns a milky white substance after just a few months. A multinational of overseas buyers in Bogota decided to make a policy (1993 – 94) not to ever accept Palm oil from any supplier. The Emerald Congress '98 in Bogota also agreed to rule Palma as an unacceptable filler. Palma resin has progressively loss its popularity. Code: E-Colourless-Resined

Opticon

The most widely known of the epoxy resins is sold under the brand name Opticon.  Since 1980 Brazilian emerald producers have been filling their emeralds with it. This was kept in secrecy for many years therefore was considered a highly unethical practice.In 1996-97 Colombian and other producers also began to use opticon.Most retailers prefer to reject an emerald with the indicative "flash effect" of opticon, preferring the natural cedar wood option.It was described as a substance that was filling the inclusions in the emeralds with green coloured resin that was inaccurately increasing the value of the stone. This is a rare case and most feel that it is very easy to detect. Opticon may turn brown or yellow inside of the stone after many months or years. The results of a broad study of various fracture-filling materials found that Opticon treatment was, (1) like the traditional materials, best detected using magnification with a variety of lighting techniques; and (2) although somewhat more durable than the traditional enhancements, was still altered in the course of routine jewellery cleaning and manufacturing processes.
Code: E-Colourless- Resined and / or T-Dyed

JOBAN

This is the treatment of choice in emeralds from India. Joban is a green oil that makes the emerald look much nicer than it actually is. Although it is considered unethical, the producers in India have admitted that Joban is "Like make-up your wife puts on". Code: T-Joban

These are the most common emerald enhancements and treatments. Remember though, an emerald's fissures is so small that the addition of one of these enhancements is so minute that it is nearly unnoticeable unless it is coloured. All the enhancement is doing in simple terms is improving the clarity by allowing light to pass through the stone with more ease and to refract back out of the crown and table.

With the exception of the normal fashioning (cutting and polishing) of a gemstone, it is the seller’s responsibility at all levels of commerce to clearly disclose to the buyer at the time of sale:

1. Whether the gemstone is natural or not;
2. All information pertinent to any enhancement process done to a natural gemstone when:
   • the treatment is not permanent and its effects are lost over time; or
   • treatment creates special care requirements for the gemstone to retain the benefit of the treatment; or
   • the treatment has a significant effect on the value of the gemstone.

In order to be certain what is in your stone it is best to have it assessed by a certified gemmologist.