PRASIOLITE vs. PRASEOLITE
Prasiolite (spelled with an “i” and sometimes spelled p-r-a-z-I-o-l-I-t-e) comes from the Greek word meaning “Leek Stone” & is sometimes incorrectly called lime citrine. It is a green variety of quartz.
It is both a naturally occurring gemstone and it is simulated from genuine quartz via heat treatment. Praseolite (spelled with an “e”) is a heat-treated, leek-green color of cordierite/iolite. Praseolite/cordierite is a different species from prasiolite/vermarine/quartz but it does have a similar leek-green (greenish to greenish yellow) in color.
The Natural prasiolite green variety quartz: Prasiolite/vermarine is a naturally occurring greenish yellow gemstone. It is speculated that heat produced naturally by geological events during formation of the mineral caused the production of the naturally green deposits. Deposits of naturally occurring prasiolite has been reported in Southern Bahia (Brazil), Canada (Thunder Bay), Poland, Tanzania, Namibia, Nevada and New Hampshire. It is often to be found side-by-side with purple amethyst crystals in igneous, metamorphic and volcanic rock. NOTE: Natural prasiolite can also be enhanced (sometimes dyed) to improve the color.
The heat-treated green variety quartz: is a heat-treated amethyst that the prasiolite name is applied to as well. It is amethyst, which contains iron compounds Fe2. It turns a pale to very pale grayish mint green after heating. They also call this "green amethyst" or "greened amethyst". Green amethyst & greened amethyst are misnomers for this artificially induced greenish variety quartz. In the case of, the improper term "green or greened amethyst" it might be better described as "heat-treated amethyst" or "enhanced quartz". The heat-treated prasiolite /green variety of quartz is not considered rare nor scarce. There is also an inexpensive irradiated form available too. Although the first suitable source of quartz to render the greenish variety (following heat-treatment) is thought to be Brazil, it is now also found in Montezuma, Zimbabwe, Arizona and the California Nevada border making it well established in the market place.
SEPARATIONS- It is very difficult to separate the heat-treated quartz from the naturally green prasiolite. Both the enhanced quartz (greened amethyst) and natural prasiolite materials are almost identical in properties. In some cases, there are a few insignificant properties that can occur which would help the trained eye in separating the two. NOTE: Some colorless quartz crystals have sufficient inclusions of chlorite to result in a green color; however, this would not be considered prasiolite.
Last Update: 23 Nov 2008