There is green quartz called ‘Greened’ amethyst or Vermarine also known as Prasiolite having light to medium color. On subsequent heating amethyst looses color and turns grey or white making it worthless. Some unusual like golden orange or Rio Grande citrine or dark sherry colored or Madeira citrine are highly prized. Much of citrine which comes from Brazil is heat-treated. ![]() This process depends on various factors including the percentage of the iron impurities present and the heating duration and time. When heated, the iron impurities are reduced to make amethyst’s purple color to fade and turn yellow to reddish-orange ( citrine). The only difference between amethyst and citrine is the oxidation state of the iron impurities present in the quartz. It was discovered long ago that by heat-treating light colored amethyst or smoky quartz a small percentage would turn into attractive golden yellow color. Most of the large darker stones exhibiting color zoning are often heat-treated to produce dramatic color changes.Ĭitrine, yellow colored quartz though occurs naturally is produced by heating amethyst with the proper iron content under controlled conditions. It is a permanent and common Amethyst treatment and last forever. ![]() This heat treatment causes inclusions to expand causing tiny fractures in the crystal surrounding them. On treating Amethyst under controlled conditions one can produce some very astonishing colors or intensify the royal purple color at 400c to 600c. Most of the amethyst available in the gem market is enhanced to get exotic shades. Very dark amethyst is heated to produce lighter shades. Heating is the most common treatment which can alter the color of a stone to lighten, darken, or change completely. The two main processes are heat treatment and irradiation which if done properly can dramatically change the Amethyst’s clarity. These are usually undetectable and somewhat irreversible processes. These human initiated processes are basically done to improve the nature and color of the stones. To enhance the beauty many gemstones are treated to various processes since antiquity. The lower grade Amethyst in light to medium color is found in Brazil. Uruguay mines produce medium grade stone having properties of medium to dark tone and moderate to strong saturation. ![]() The Siberian stones belong to higher grade outclass all other competitors in richness and depth of their violet and purple hues. These stones are graded according to clarity and color. Some dark colored small sized amethysts are mined in Australia also. The stones from the mines of South America are usually larger in size but the African stones are considered better in color and saturation. Most of these stones are mined in Latin American countries like Brazil, Uruguay, Argentina and Bolivia as well as in some African countries like Zambia and Namibia. This hard and versatile stone is available world wide however different regions produce their own unique varieties. Amethyst are available in wide range of sizes, shapes and colors from deep purple which are considered valuable particularly a rich purple with rose flashes to pale colors like Lilac. Generally cut in a six sided prismatic crystal shape it produces a sparkling cluster. Its brilliant color is therefore often compared with most expensive gemstones. It also has iron content which adds variation to the colors. Violet and Purple varieties of Amethyst are considered as symbol of heaven, as they are related to the constellations of Pisces and Aries.Īmethyst is transparent quartz having the presence of manganese, which produces the stunning purple color. Considered as a strong antidote against drunkenness it literally meant ‘not to intoxicate’ in ancient Greece. ![]() Amethyst was considered symbol of celibacy and piety by the Christian Priests in the western countries. The healing and magical properties of Amethyst made it valuable right from the middle Ages. Amethyst being birth stone for the month of February is the common quartz used in jewelry. It was the favorite stone of British monarchy and sparkled in the crown of Catherine the Great and ancient Egyptian royals. Different Amethyst Treatment, its Effect and respective Commercial ValueĪmethyst has been the most sought after stone from time immemorial.
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