Gemstone Enhancements
Assembled
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
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
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
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
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.
Fissure Filling
To improve durability or appearance or to add weight. Like getting a filling at the dentist gemstone fissure filling introduces material to fill surface-breaking cavities or fissures within a gemstone. Fillers may consist of colorless glass plastic solidified borax or similar substances. These substances are typically fused with the original gemstone material through a heating process.
Heat
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.
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.
Impregnation
To improve durability and appearance. Occasionally porous gemstones are impregnated with a colorless agent or polymer to stabilize a gemstone making it more durable and suitable for lapidary work.
Irradiation
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.
Lasering
To improve clarity. Typically used to enhance diamonds a high powered laser burns a hole in a colored inclusion in the stone. Then a chemical what removes the coloring agent improving the overall clarity of the gemstone.
Oiling
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.
Plated
To enhance the appearance protect the surface or strengthen. The surface of the gemstone is covered with a thin coating or film typically in a metallic material.
Polymerization
To improve durability and appearance. This form of enhancement uses the chemical bonding of two or more monomers to form polymers which are used as bonding agents.
Stabilisation
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
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
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.