No indication of enhancement.
No gemological constraints (for instance no altered inclusions) are present which would indicate that a heat enhancement process was applied.
Indication of enhancement. (H)
(H). gemstone subjected only to thermal treatment, which changed its physical properties, including the degree of transparency and color and will always be mentioned on the report.
Clarity Enhancement/Indication of fissure.
Any opal that show indications of having any filling of fissures with resins, wax or any other filler, and will always be mentioned on the report.
- Insignificant
- Minor
- Moderate
- Significant
Smoke treated Opal
The term “sugar treatment” refers to carbonization. Also, because there are other methods to change base color of matrix opals than just boiling in sugar and acid and the result is the same: filling pores with carbon (Color modification by smoke treatment) and will always be mentioned on the report.
Assembled Opal.
(Assembled Opal).– gemstone consisting of two or more parts of natural, modified or reconstructed amber bonded together with the use of the smallest possible amount of a binding agent necessary to form a single pieces and will always be mentioned on report.
Opal Doublet
They are created when a layer of precious Opal is glued to a backing that is strong. Usually it is ironstone, black potch or plastic.
In many cases the Opal is too thin to use by itself so it is glued to a backing to add strength and will always be mentioned on the report.
Opal Triplet
The Opal used in a triplet is thinner than that used in a doublet and so the top of the Opal also also needs to be protected by a piece of clear Quartz or black plastic or potch and will always be mentioned on the report.
Foil opal (Man -made)
are simulated opal gemstones The term 'foil' refers to an actual metal foil that was sometimes used to create reflection and sparkle behind milky glass or quartz faces and will always be mentioned on the report.
Dyeing
Any opal that show (Evidence of color is modified by dyed or color substance) and will always be mentioned on the report.