Amethyst
is a violet variety of quartz often used in jewelry. The name comes from the Ancient Greek a-
("not") and methustos
("intoxicated"), a reference to the belief that the stone protected its owner from drunkenness; the ancient Greeks and Romans wore amethyst and made drinking vessels of it in the belief that it would prevent intoxication.
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AMETHYST TICKETS
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Chemistry
Amethyst is the violet variety of
quartz; its chemical formula is SiO
2.
In the 20th century, the color of amethyst was attributed to the presence of
manganese. However, since it is capable of being greatly altered and even discharged by heat, the color was believed by some authorities to be from an organic source.
Ferric thiocyanate was suggested, and
sulfur was said to have been detected in the mineral.
More recent work has shown that amethysts' coloration is due to ferric
iron impurities.
[1] Further study has shown a complex interplay of
iron and
aluminium is responsible for the color.
[2]
On exposure to heat, amethyst generally becomes
yellow, and much of the
citrine,
cairngorm, or yellow quartz of jewelry is said to be merely "burnt amethyst". Veins of amethystine quartz are apt to lose their color on the exposed outcrop.
Synthetic amethyst is made to imitate the best quality amethyst. Its chemical and physical properties are so similar to that of natural amethyst that it can not be differentiated with absolute certainty without advanced gemological testing (which is often cost-prohibitive). There is one test based on "Brazil law twinning" (a form of
quartz twinning where right and left hand quartz structures are combined in a single crystal
[3]) which can be used to identify synthetic amethyst rather easily. In theory however it is possible to create this material synthetically as well, but this type is not available in large quantities in the market.
Composition
Amethyst is composed of an irregular superposition of alternate
lamellae of right-handed and left-handed quartz. It has been shown that this structure may be due to mechanical stresses.
Because it has a hardness of seven on the
Mohs scale, amethyst is suitable for use in jewelry.
Hue and tone
Amethyst occurs in primary hues from a light pinkish violet to a deep purple. Amethyst may exhibit one or both secondary hues, red and blue. The ideal grade is called "Deep Siberian" and has a primary purple hue of around 75–80 percent, 15–20 percent blue and (depending on the light source) red secondary hues.
[4]
History
Amethyst was used as a
gemstone by the ancient
Egyptians and was largely employed in antiquity for
intaglios. The Greeks believed amethyst gems could prevent
intoxication, while medieval European soldiers wore amethyst
amulets as protection in battle. Beads of amethyst were found in
Anglo-Saxon graves in
England.
A huge geode, or "amethyst-grotto", from near Santa Cruz in southern
Brazil was exhibited at the
Düsseldorf, Germany Exhibition of 1902.
Amethyst is the traditional
birthstone for February.
Mythology
The Greek word "amethystos" may be translated as "not drunken", from Greek
a-
, not +
methustos
, intoxicated
[5]. Amethyst was considered to be a strong antidote against drunkenness, which is why wine goblets were often carved from it. In Greek mythology,
Dionysus, the god of intoxication, was pursuing a maiden named Amethystos, who refused his affections. Amethystos prayed to the gods to remain chaste, which the goddess
Artemis granted and transformed her into a white stone. Humbled by Amethystos's desire to remain chaste, Dionysus poured wine over the stone as an offering, dyeing the crystals purple.
Variations of the story include that Dionysus had been insulted by a mortal and swore to slay the next mortal who crossed his path, creating fierce tigers to carry out his wrath. The mortal turned out to be a beautiful young woman, Amethystos, who was on her way to pay tribute to Artemis. Her life is spared by Artemis, who transformed the maiden into a statue of pure crystalline quartz to protect her from the brutal claws. Dionysus wept tears of wine in remorse for his action at the sight of the beautiful statue. The god's tears then stained the quartz purple.
[6] Another variation involves the goddess
Rhea presenting Dionysus with the amethyst stone to preserve the wine-drinker's sanity.
[7]
Geographic distribution
Amethyst is produced in abundance from the state of
Minas Gerais in
Brazil where it occurs in large
geodes within
volcanic rocks. It is also found and mined in
South Korea. The largest opencast amethyst vein in the world is in Maissau, Lower Austria. Many of the hollow agates of Brazil and
Uruguay contain a crop of amethyst crystals in the interior. Much fine amethyst comes from
Russia, especially from near Mursinka in the
Ekaterinburg district, where it occurs in drusy cavities in granitic rocks. Many localities in
India yield amethyst. One of the largest global amethyst producers is Zambia with an annual production of about 1,000 t.Amethyst occurs at many localities in the
United States. Among these may be mentioned Mazatal Mountain region in Arizona is the only US location that currently mines fine quality gems that are sold in fine jewelry. Amethyst Mountain,
Texas;
Yellowstone National Park;
Delaware County, Pennsylvania;
Haywood County, North Carolina; Deer Hill and Stow,
Maine. It is found also in the
Lake Superior region. Amethyst is relatively common in
Ontario, and in various locations throughout
Nova Scotia, but uncommon elsewhere in Canada.
Value
Traditionally included in the cardinal, or most valuable, gemstones (along with
diamond,
sapphire,
ruby, and
emerald), amethyst has lost much of its value due to the discovery of extensive deposits in locations such as
Brazil. The highest grade amethyst (called "Deep Russian") is exceptionally rare and therefore its value is dependent on the demand of collectors when one is found. It is however still orders of magnitude lower than the highest grade sapphires or rubies (
Padparadscha sapphire or "pigeon's blood" ruby).
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See also
Notes
- Klein, Cornelis and Hurlbut, Cornelius S., 1985 ''Manual of Mineralogy (after JD Dana)'' 20th edition, p. 441, John Wiley & Sons, New York
- Cohen, Alvin J., 1985, ''Amethyst color in quartz, the result of radiation protection involving iron', American Mineralogist, V. 70, pp 1180-1185
- Quartz Page Twinning Crystals
- ''Secrets of the Gem Trade; The Connoisseur's Guide to Precious Gemstones'' Richard W Wise, Brunswick House Press, Lenox, Massachutes., 2003
- The American Heritage Dictionary
- http://gemstone.org/gem-by-gem/english/amethyst.html source
- (Nonnus, ''Dionysiaca,'' XII.380)
References
- Klein, Cornelis and Hurlbut, Cornelius S., 1985 ''Manual of Mineralogy (after JD Dana)'' 20th edition, p. 441, John Wiley & Sons, New York
- Cohen, Alvin J., 1985, ''Amethyst color in quartz, the result of radiation protection involving iron', American Mineralogist, V. 70, pp 1180-1185
- Quartz Page Twinning Crystals
- ''Secrets of the Gem Trade; The Connoisseur's Guide to Precious Gemstones'' Richard W Wise, Brunswick House Press, Lenox, Massachutes., 2003
- The American Heritage Dictionary
- http://gemstone.org/gem-by-gem/english/amethyst.html source
- (Nonnus, ''Dionysiaca,'' XII.380)