GEMSTONE ENHANCEMENTS
Gemstone enhancement has a long tradition and is a widely accepted practice in the jewelry industry. While some stones do not need any enhancement or treatments to look their best many others sold today require some form of conditioning or alteration to make the stone 'market ready.'
Customarily enhancements enrich the appearance of the gemstone. These techniques can improve the color clarity and durability of the gemstone. Enhancement processes vary based on the stone's characteristics and the necessary treatments required for bringing out the beauty of each stone. This list of common enhancements can help you identify what enhancement your gemstone jewelry may have undergone and how to best care for your purchase to keep it looking its best for years to come.
Assembled: A
To improve durability or
appearance. Assembled gemstones consist of two or more parts where at least one of these is a natural
gemstone like in a doublet or triplet construction. The colored stone is sandwiched between a dark glass
or semi-precious stone base and a protective natural crystal cap. This new three-layered stone is more
resistant to impact and scratching than the original material.
Bleaching: B
To lighten or remove color. Heat
light and/or other chemical agents are applied to the original material. This is especially common with
pearl jewelry to remove discoloration on the surface of the pearl.
Coating: C
To improve appearance add color or
other special effects. Surface enhancements like lacquering enameling inking foiling or sputtering of
films are common in jewelry design. Modern gem coatings are indistinguishable from the gemstone like the
coatings that are applied to eyeglass lenses. A prime example of a coated gemstone is the popular mystic
topaz. An iridescent coating gives these stunners their signature rainbow radiance.
Diffusion: DF
To change color and/or introduce
asterism-producing inclusions. Diffusion enhancements are often undetectable on a microscopic level.
Chemical elements in conjunction with high temperatures are introduced to the molecular structure of a
gemstone. For example in natural gemstones the element chromium is typically responsible for a stone's
green hue. By diffusing chromium to a neutral base material you can transform it into a green gemstone.
Dyeing: D
To enhance or change color. One of
the oldest gemstone enhancements dyeing introduces pigment into a gemstone to give it new color
intensify its original color or improve color uniformity. Chalcedony quartz and agate are commonly dyed
to produce a popular variety of colors. While these dyes are stable you should take extra care to avoid
prolonged exposure to moist heat.
Heat: H
To alter color or improve clarity. One
of the most common gemstone enhancements heat c is slowly applied to gemstones at temperatures ranging
from 200 to 2 000 degrees Celsius. Gemstones are formed under heat and pressure and this heat-only
treatment can act as a continuation of Mother Nature's original design.
High Pressure High Temperature: HPHT
To alter
color clarity or phenomena. Like heat-only treatments high-pressure high-temperature treatments (HPHT)
mimic the natural conditions under which gemstones are formed. This combination of heat and pressure can
lighten deepen or transform the color of a gem depending on the original material. The heat and pressure
can also mend certain flaws or inclusions.
Irradiation: IR
To alter color. In a laboratory
setting a gemstone is bombarded with subatomic neutrons gamma rays or beta particles (high energy
electrons) to alter the molecular structure of the gemstone material. The irradiation process is very
safe and leaves no residual radioactivity in the gemstone material. Occasionally this treatment may be
followed by a heating process for added stability.
Oiling/Resin Infusion: O
To improve clarity and
surface texture. Similar to fissure filling the technique of infusing a gemstone with oil resin wax or
other colorless substances improves the overall appearance of the stone. Glass and plastic are not used
in the oiling/resin infusion technique.
Stabilization: S
To stabilize hardness and
clarity. Stabilization is not a color enhancement. In this process excess gemstone material and clear
resin are mixed and applied to the original porous gemstone material. This color matched mixture
protects the gemstone while allowing it to retain its natural color.
Waxing/Oiling: W
To enhance luster. The surface
of porous opaque or translucent gemstones is rubbed with a colorless wax paraffin or oil in to improve
the surface quality and add a shiny luster.
Zachery: Z
Turquoise is a porous gemstone and
the Zachery treatment is a proprietary enhancement process used to decrease its porosity. This treatment
prevents oxidation and discoloration of the stone due to agents like skin oils cosmetics and sweat that
the stone is exposed to during typical wear. This technique also improves the stones ability to take a
good polish and may improve the stone's color.
