Peridot Buying Guide
Despite peridot’s popularity as a jewelry stone, discerning consumers may find most of this material to be low quality. Many stones have an overly olive color and receive poor cuts and polishes. However, give this gemstone a second look. With custom gem cutting and proper polishing, these beautiful lime and apple green gems will earn your appreciation.
Peridot Buying and the Four Cs
The IGS peridot value listing has price guidelines for faceted pieces.
Peridots come in many shades of green, and only green. The highest values go to gems with yellowish green hue, medium tone, and moderately strong saturation. (For more information on color descriptions, see our guide to GIA color codes).
However, if you like green, you can probably find a peridot that matches the color you want. Peridots can show deep, emerald-like colors as well as almost neon brightness. Different localities produce different shades of green. Consult the information on sources in our peridot gem listing for more information.
Most peridots are usually eye clean. That means they have no inclusions (materials, cavities, or fractures inside the gem) visible to the naked eye. Nevertheless, most peridots do contain inclusions visible under magnification, including their distinctive “lily pads.” Eye visible inclusions will likely lower a peridot’s value, as will the presence of many inclusions, which create a cloudy effect.
Be advised that those distinctive lily pad inclusions can make peridots difficult to cut. They can be hard to spot when faceting and can act like cleavage planes. If you’re considering purchasing rough for faceting, have an expert examine it first.
Editor’s Note: To hide inclusions in peridots, Jeff Graham recommends checkerboard cuts. For clear peridots, a cornered cut can work well. Search his gemstone faceting diagrams for more peridot friendly designs.
Peridots have high birefringence, which can cause fuzziness. To prevent this out-of-focus appearance of reflections through the table facet, lapidaries must orient the stone carefully before cutting. Some peridots also have a weak pleochroic effect, showing green/yellow-green colors depending on the viewing angle. This factor can also affect gem orientation.
Most peridot rough produces quite inexpensive stones under one carat. Rare large sizes, over three carats, increase exponentially in value.
Jewelry Considerations when Peridot Buying
Peridots can work well in almost any type of jewelry, but you should take some precautions. Some of these gems may split if struck by a sharp blow due to their cleavage. With a hardness just below that of household dust (mostly quartz), peridots can show scratches rapidly and chip easily. Thus, ring stones should have protective settings, like bezels. In addition, avoid placing peridots in tension settings, since the stress may cause them to split.
Peridots also have some heat and acid sensitivity. Avoid sudden increases in heat, which could shatter them, and prolonged wear against the skin. Of course, avoid any cleaning agents with acid as well as mechanical cleaning systems such as ultrasound, steaming, or boiling. For cleaning, use only a soft brush, mild detergent, and warm water.
Best Sources for Peridot Buying
Historically, Egypt has been the most important source for gem material. More recently, Arizona, China, and Pakistan have superseded Egypt as sources. Myanmar produces very large peridots.