Oiling is a process of applying mineral oil to a stone, and is used to mask inclusions or enhance the color of a stone. Emeralds, although very valuable are typically infused with inclusions. Emeralds are typically oiled to improve quality.
This technique is commonly used on emeralds. The purpose of this technique is for the oil to fill the fine cracks that weaken the green color. The oil fills the cracks making them "disappear" and thereby improving the color.
Oiling is used to seal a stone such as opal from water loss. It is used to fill fissures on the surface of emeralds, improving their clarity.
Oiling infuses colorless oils, resins and waxes into tiny surface-breaking fissures to hide them and give gems a clean-complexioned appearance. This long-practiced clarity enhancement is used mainly for emerald and jade. The oils used are either natural or have a natural counterpart. If coloring agents are added to the oil, the stones are classified as dyed. Emeralds infused with man-made substances like plastics and polymers that have no natural counterpart are considered impregnated. For a list of stone treatments, frequency and stability of treatments, and care instructions, visit our Gemstone Enhancements and Treatments chart.
A common procedure for gemstone color enhancement. The treatment is not permanent and should be disclosed at point of purchase.
Oiling is a process of applying mineral oil to a stone in order to enhance it and mask inclusions, make them more transparent, and darken their color. Emeralds are frequently oiled to mask their many inclusions.
The process of applying mineral oil to a stone, such as an emerald, to mask inclusions and enhance the color.