Gemstone treatments are very common. When gemstone rough material is mined, there are often imperfections in the material, which will negatively impact the stone’s brilliance after it’s cut. Also, the rough material’s color may be dull and when cut, the stone will not be attractive. Therefore, many gemstones are treated to either enhance it’s color and/or clarity. Some treatments are standard and do not impact value of a gemstone, while others may improve the look of a stone, but negatively affect a stone’s value. 

Below is a list of common treatments: 

Heat: Heat treatment means that the gemstone was placed in an oven at a low temperature (usually 450 degrees) to bring out its natural color. Heating a stone does not alter its chemical composition whatsoever, nor is it considered to be a synthetic enhancer. Heat is the most common treatment, and is the most universally accepted treatment by gemstone dealers as a natural treatment. Gemstones that are heated will still be referred to as “natural.” Heat does not affect the overall stability of the gemstone, nor does it affect the gemstone’s value. Commonly Heated Gemstones: Paraiba Tourmaline, Tanzanite, Ruby, Sapphire, Emerald, Aquamarine, Tourmaline, Morganite. 

Oil: Oil is used as a clarity enhancer. Essentially, oil will fill in the fissures of a gemstone with imperfections. This improves the gemstone’s clarity. Oil generally does not affect the overall stability of a gemstone, but over a long period of time, it may be beneficial to re-oil a gemstone if need be. Oil will negatively affect the value of a gemstone, unless it’s a gemstone that is typically oiled as a standard treatment. Commonly Oiled Gemstones: EmeraldRadiation: 

Radiation is used as a color enhancer. Many gemstones may benefit from irradiation when Heat treatment alone doesn’t bring out the gemstone’s color enough. Stones are place under a radiation lamp and the color can be enhanced dramatically. Radiation is a semi-permanent treatment. Over time, the color of a radiated gemstone can fade, however the color rarely fades back to it’s original non-radiated color. Commonly Radiated Gemstones: Blue Topaz, Kunzite, Yellow Beryl (Heliodor) 

Below is a list of other treatments that are less common: 

Bleaching

Coating

Dying

Filling

HP (Heat & Pressure)

Impregnation

Lasering

Diffusion

Waxing

Assembling

Composite treatment