What you should know about Gemstone Treatments
Are they really such a bad thing.
Buyers should assume that Rubies and Emeralds have been heat treated. Heat Treatments are used to remove rutile inclusions and improve color, tone and Saturation.
Since this treatment is not unlike natural processes that occur in nature,it does not negatively impact price or value of gems.
Diffusion treatment leaves a thin layer of color on the outside layer of the gem. It improves the color on transparent gems and can enhance asterism. This is a fairly common treatment for Star Sapphires and Star Rubies . Diffusion treatment is only seen when the stone is immersed in an RI liquid. Diffusion treated gems show color concentrations around the facet edges. This is subtle and its visibility can be washed out if your light is too bright. A untreated Star gem is not very attractive. This treatment is to enhance the star and will last forever.
Smoke treatment is a relatively old method of stone treatment that has just recently been reinvented.
The process involves wrapping opals into silver foil strips and slowly heating them, allowing the buildup of smoke inside the foil.
Carbon formed by the smoke, penetrates deep into the opal stone and stains the original color with deeper and darker tones. Smoke treatment is intended to give the opal brighter play of color, because the bright colors contrast better on darker backgrounds.
Buyers should assume that most Rubies and Emeralds have some Lead Glass filling. This process corrects minor defects in the gem and makes them attractive. The human eye cannot tell the difference. This makes it possible for most buyers who want these gems without paying many thousands of dollars. Unfilled gems sell for $10,000 to $ 100,000.
Irradiation produces yellow and orange from light colored material. It is rarely used and, since it duplicates natural processes, it is undetectable.