What is an oil treatment for emeralds?
Jan 22, 2019 · The traditional treatment for emerald is oiling with cedar oil. Cedar oil is a natural product from cedar trees and is colorless and viscous. It can be produced in a very pure form and has a number of industrial uses. It is used as an immersion oil in light microscopy, as an ingredient in insect repellents, as an anti-bacterial and as a food ...
Can you re-oil emeralds?
Oiled Ruby: A Remarkable Visual. E. Billie Hughes Download PDF ... Thailand, it is sold under the brand name “King Ruby Red Oil”). Often this treatment can be identified by flattened gas bubbles in the fissures or by droplets of oil seeping out of the fissures on the surface when the stone is gently warmed by microscope light or hot point. ...
What is the best oil to use for Emerald fractures?
Oil treatments are also used to enhance color. Emerald ring, photo by Mauro Cateb. Licensed under CC By 2.0 To re-oil emeralds, all you need to do is submerge the stone in an appropriate solution (oil, epoxy, etc). Next, place the stone and the solution somewhere warm. The back of a stove or a sunny window in summer are great locations.
How do you treat emeralds with fissures?
Green garnets from Tanzania, tsavorites don’t get very large. The trade would consider a 5-ct cut stone very large, while 1-ct stones are fairly common. However, their color rivals emerald’s, and you can usually find them clean, whether rough or cut. Usually, they receive no treatments. Also, these gems can match or exceed emeralds in hardness.
What does it mean when an emerald is oiled?
Over 99% of emeralds have surface reaching fractures that are treated with oil, wax, resin, or something else entirely. This is done to improve the clarity of emeralds, and usually termed as enhancement instead of treatment is the sales sector of the gem industry. Labs will instead use terms such as treatment.
Are oiled emeralds worth anything?
If it belongs to the 'moderate' category, the value varies from $8000 – $12,000 per carat. Finally, an emerald displaying 'significant' indications of treatment could be worth from nothing to $4000 – $6000 per carat.Aug 24, 2016
What does it mean when a gemstone is oiled?
Oiling gemstones to fill internal fractures is a common practice. Many different oils are used for emerald fractures. For example, using colorless cedarwood oil is a supposedly acceptable practice. Colored oils are also used.
What is the process of oiling an emerald?
To re-oil emeralds, all you need to do is submerge the stone in an appropriate solution (oil, epoxy, etc). Next, place the stone and the solution somewhere warm. The back of a stove or a sunny window in summer are great locations. Keep it at about 100° F for a day or two.
Why are emeralds heat treated?
Instead, Emeralds are typically treated with oil or other "fillers". The purpose of this is to draw the filling substance into any surface-reaching fissures (on a microscopic level) to improve the clarity of the Emerald.
Are Colombian emeralds treated?
Since emerald treatment primarily reduces the visibility of fractures that penetrate the stone from the surface, many fine-quality Colombian emeralds are not treated because of their higher clarity.
How do you tell if an emerald has been oiled?
Fracture-Filled Emerald Inclusions Look Like: Oil might have a slightly yellowish or brownish color.Jun 17, 2013
Do emeralds scratch easily?
Contrary to popular belief, emeralds are very resistant to scratches. A direct measure of this is the Mohs Hardness Scale. Any mineral on the scale can be scratched by a mineral the same rank or above it, but cannot be scratched by anything below it.
Do you need to oil emeralds?
Things You'll Need Oiling emeralds gives them a high sheen. Natural emeralds are riddled with fissures and cracks before treatment. Some are also slightly cloudy or opaque in patches due to the natural process of emerald formation.
Can you use ammonia to clean emeralds?
EMERALDS ARE A hard gemstone (a member of the beryl gem family), but they require a delicate touch when it comes to cleaning them. When cleaning emeralds, traditional cleaning products, most with harsh ammonia are NOT recommended.May 2, 2013
What is no oil emerald?
No Oil Emerald is a rare and extremely valuable variety of emerald gemstone which is not clarity enhanced by the additional of any oil. These gems are naturally clean and have no fracture at the surface. This leaves no chance for a 'foreign' material (oil or resin) to get inside the stone.
What is Opticon resin?
Opticon is a plastic polymer resin. It’s injected onto and into emeralds, both rough and cut, often under a vacuum. Although this treatment has more stability than oiling, it will yellow and disintegrate with age and some solvents. It fills flaws and helps improve color and some durability.
What is the difference between a type II and a type III?
Type IIs usually possess inclusions, while Type IIIs almost always do. (Emerald belongs in the Type III category). Although stones can receive the same clarity grades, the grades have different meanings based on the stone category. This GIA model holds that you can’t compare all gemstones to each other.
Do oils wear off emeralds?
This is usually to the buyer’s loss. Sooner or later, oils will wear off (and out of) emeralds. In other words, the “improvement” isn’t permanent. When it wears off, your stone will probably look terrible.
Can you cut synthetic emeralds?
Personally, I don’t like cutting synthetic rough. However, if you really want to have a professional lapidary cut an emerald for you, choose hydrothermally grown synthetic emeralds. Truthfully, they make good replacements, especially when you consider all the dyes, oils, and other emerald treatments the natural gems receive.
Is chrome tourmaline more durable than emerald?
Chrome Tour maline. Harder and more durable than emerald, chrome tourmaline, rough or cut, is found more easily and for less money than both tsavorite and emerald. If you’re buying rough, watch the color. This tourmaline variety can have very intense saturation, which might make for a very dark green gem.
Is diopside hard enough for earrings?
The green chrome variety of diopside has a lower hardness than emerald and a refractive index (RI) of 1.67-1.72. For jewelry applications like rings, it’s just not hard enough. However, it should work fine for earrings and pendants. You can find it easily and inexpensively in small sizes (1 to 2 gram material). Be aware that larger stones tend to be darker in color. These gems usually receive no treatments.
Is a stone more fragile than it appears?
Of course, this is why the treatment is done in the first place. However, these concealed flaws could make the stone more fragile than it appears. It may even be unsuitable for jewelry use.
About the Author
E. Billie Hughes visited her first gem mine (in Thailand) at age two and by age four had visited three major sapphire localities in Montana. A 2011 graduate of UCLA (B.A., Political Science), she qualified as a Fellow of the Gemmological Association of Great Britain (FGA) in 2013.
Notes
This article first appeared in Gems & Gemology, Summer 2017, Vol. 53, No. 2.
About the Author
E. Billie Hughes visited her first gem mine (in Thailand) at age two and by age four had visited three major sapphire localities in Montana. A 2011 graduate of UCLA (B.A., Political Science), she qualified as a Fellow of the Gemmological Association of Great Britain (FGA) in 2013.
Notes
This article first appeared in Gems & Gemology, Summer 2017, Vol. 53, No. 2.
What is the best oil to use on emeralds?
The traditional treatment for emerald is fracture-filling with natural oils. Cedarwood oil is most commonly used, because it is colorless and has a refractive index close to emerald. But the oil can dry out and emeralds have to be re-oiled from time to time to keep them looking their best.
What color are emeralds?
Emeralds tend to be among the most included of all natural gemstones. The inclusions are tolerated because the finest emeralds display a vivid bluish-green color that is quite unique in the gems world. But in many cases the various internal gas bubbles, embedded crystals, veils and cracks make the emerald look cloudy or milky.
What is Opticon resin?
Opticon, an expoxy prepolymer, has better stability than cedarwood oil, and a refractive index almost identical to emerald.
What is the treatment for corundum?
Sapphires or corundum undergo various treatments ranging from heat only (sometimes this is referred to as low heat although the temperature isn't low at all), diffusion (heated to almost melting point and minerals are added to alter the original colour), clarity enhancement and irradiation.
Why do sapphires need oil?
This treatment enables gem dealers to sell a larger stone (at a higher price) because fractures that might otherwise have to be cut away are filled with oil. Oil fillers are not stable and will evaporate over time, leaving a less attractive stone with readily apparent fractures. This treatment is coming into use and is often not disclosed by the gem supplier.
What is flux healing?
Flux healing involves heating corundums with borax or other fluxes. These fluxes actually dissolve the surfaces, including the internal surfaces of cracks. The corundum within this molten material then re-deposits on the fracture surfaces, filling and healing the fractures shut.
Is ruby unheated or inert?
Doing this test requires a good bit of gemological knowledge though and just because a ruby might be inert, that does not mean it is unheated. The stone also has to be clean before testing because soap and other chemicals can produce chalky fluorescence. This test is not definitive and should be ONE of the testing methods used together with a complete gemological examination in a fully equipped lab.
Is corundum rare?
Only corundum in attractive colors and color saturation levels is rare. There are large deposits of sapphire that can produce large stones in unmarketable colors. Conventional heat treatment can improve only a very small percentage of such material.