Are gems being treated unfairly?

[Many of the colored gemstones on the market today have been treated to enhance their beauty and durability.]

To be clear, a treated gemstone is still a real gemstone, but it has been enhanced for greater value. Commonly, heat treating gems is used to alter the color of the gem. Bright blue topaz, blue-violet tanzanite, and the deep red of rubies are all examples of gems that are extremely rare in nature.

Most jewelers do sell treated goods. The practice is considered ethical only as long as any treatments are disclosed and their degree of permanence taken into account when pricing the gem. Listed below is a list of treatments that require disclosure by the Federal Trade Commission, some are not so eco-friendly:

• Bleaching (hydrogen peroxide, diluted acid, chlorine bleach)
• Cavity filling to seal cracks with glass or plastic
• Colorless impregnation of melted wax or plastic to fill the pores of a gem
• Chemicals or colored oils are used to add color or to deepen it
• Fracture filling to seal narrow breaks and improve clarity
• Irradiation
• Lattice diffusion 
• Sugar and smoke treatments

Gluing various backings, such as foil, fabrics, or even feathers, onto the undersides of stones is also a common practice to enhance color or give color where there was none. Coatings such as wax or varnish bring out the luster of porous stones. Painting is also used to improve a gem’s color. A little dab of nail polish on the underside of a gem can give an inexpensive colorless gem the appearance of a ruby.

Some treatments, such as heat and irradiation, are undetectable even by gemologists. Heat treatments can lighten, darken, or change the color of a gem entirely. Often, brilliant yellow, pink, and red diamonds are those that were originally a dull grey, but that have been treated for marketability.

It is ok to purchase a treated gem, but do so knowingly. Assume a colored gemstone is treated until proven otherwise.

Lab-created diamonds and gems are not treated as the rich color is inherent in the growth process. That is indeed one of the reasons why lab-grown gems are gaining in popularity.

[content provided by Fine Jewelry News]