Inclusions in Emeralds
E1646 | medium | right | play | “Emerald ID: E1646 – Weight: 1.13 Carats – Origin: Colombia”In order to understand emerald inclusions, you must understand their clarity first. Emeralds are classified as a Type III gemstone. There are three types grouped as Type I, Type II, and Type III gems. Type I gems typically form very clearly with no inclusions. Aquamarines, heliodor, and topaz are a few examples. Most gems qualify as Type II gems, usually showing some inclusions. Rubies, sapphires, and quartz are all examples of Type II gems. Type III gems almost always show inclusions, which is the category emeralds fall into. As a result most emeralds are oiled for clarity.
The French have a term for these typical inclusions, called a “jardin” or “garden”. Inside the green gem these inclusions resemble a garden, with both being creations of mother nature. No two sets of inclusions are the same, and are even capable of identifying individual gems.
Inclusions in emeralds are sometimes referred to as “jardin,” or “garden” because they can resemble moss or plant foliage. Emeralds with many inclusions should be treated with care, since they are more vulnerable to damage due to the inclusions. Despite these, they are still far more durable than your finger.
Inclusions form due to the fact mother nature mixes whatever random elements are in the ground. Beautiful, transparent gems are the lottery prize of these formations. Of course different locations will have different inclusions, though source-specific inclusions do not form in every emerald. Emerald inclusions vary with their and may be used as a diagnostic tool for assessing the country of origin. Fractures and liquid inclusions are the most frequent, but inclusions in emeralds include can be any combination of the following:
These are natural crystallizations of other minerals inside the emerald. There are as many possible crystal inclusions as there are crystals. It is also possible to find a halo surrounding these inclusions too, caused due to a difference in melting temperatures of the crystal and the emerald during formation.
It is very common to have liquid inclusions in emeralds. They can also form in cavities with a gas bubble to form a two phase inclusion. Especially common in emeralds is a three phase inclusion where a gas, liquid, and crystal formation
While more characteristic of rubies or sapphires, fingerprints are very possible in emeralds too. They often resemble the fingerprints we use to identify ourselves, though they can also look like wispy veils. Their appearance is a range, with this applying to most inclusions too.
Fingerprints can form with liquid and a gas inside them, making them two phase inclusions too.
Needles – Needles are long thin crystals. Hollow growth tubes leftover from crystal formation also fit the definition.
These are fissures and cracks are by far the most common inclusion in emeralds. No one is entirely sure why they are so common in emeralds. One idea being they are a natural byproduct of the crystal formation process, another is they are caused by harsh mining techniques.
The vast majority of emeralds are treated with oils and resins to enhance clarity issues caused by fractures. Between the oil and the fractures, they are to never be cleaned in an ultrasonic cleaner. This will remove the oil and will likely damage the emerald too. Re-oiling emeralds is not something that can be done at home either, and requires specific oil and equipment.
While not as common in emeralds as other gems like sapphires or tourmalines, color zoning refers to different amounts of coloring in the emerald. Like one side is missing color and the other side is green. While this is an extreme example and very unlikely in emeralds, it is technically possible.
Sometimes emeralds may have features that allow for them to display a phenomena called chatoyancy. More commonly called cat’s eye, this is caused by many fine needles or tubes being parallel to one another. The byproduct of this is a cat’s eye.
There has been an instance of an emerald that displays asterism, the star effect. However this is not common in emeralds. It is also not to be confused with trapiche emeralds. Trapiche emeralds are a result of crystal formation, not inclusions