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Gem
Trivia
Value
A gemstone is prized especially for great beauty or perfection. Hence,
appearance is almost the most important attribute of gemstones. Characteristics
that make a stone beautiful or desirable are colour, unusual
optical phenomena within the stone, an interesting inclusion such as a
fossil, rarity,
and sometimes the form of the natural crystal. In terms of beauty, it is
unsurprising that diamond is prized highly as a gemstone, since it is the
hardest substance known and is able to reflect light with fire and sparkle when
faceted. However, it is important to understand that diamonds are far from rare
with millions of carats mined each year.Traditionally, common gemstones were classified into precious stones (cardinal
gems) and semi-precious stones. The former category was largely
determined by a history of ecclesiastical, devotional or ceremonial use and
rarity imposed by the limits of known deposits and available collection methods.
Only five types of gemstones were considered precious:
diamond,
ruby,
sapphire,
emerald, and
amethyst.
In current usage by
gemmologists,
all gems are considered precious, although four of the five original
"cardinal gems" are usually—but not always—the most valuable.Another category of gemstones which is still in use is that of rare or
unusual gemstones, generally meant to include those gemstones which occur so
infrequently in gem quality that they are scarcely known except to connoisseurs.
Here are included andalusite, axinite, cassiterite, clinohumite, iolite, among
others all of which are durable, rare, and in better examples quite attractive.
Factors Influencing Esteem
The factors influencing the esteem in which gems are held are few in number
but extremely important because they so directly affect value. These are
attractiveness, durability, rarity, fashion, and size. They are not fixed in
scope by any means and the predominance of one factor may compensate for
shortcomings in another.
Synthetic and artificial gemstones
Some gemstones are manufactured to imitate other gemstones. For example,
cubic zirconia is a synthetic
diamond simulant composed of
zirconium
oxide. The imitations copy the look and colour of the real stone but possess
neither their chemical nor physical characteristics. However, true synthetic
gemstones are not necessarily imitation. For example, diamond,
ruby,
sapphire
and
emerald
have been manufactured in labs, which possess very nearly identical chemical and
physical characteristics as the genuine article. Synthetic
corundums,
including ruby and sapphire, are very common and they cost only a fraction of
the natural stones. Smaller
synthetic diamonds have been manufactured in large quantities as industrial
abrasives
for many years. Only recently, larger synthetic diamonds of gemstone quality,
especially of the coloured variety, have been manufactured.
This article is licensed under the "GNU Free Documentation License". It uses material from the Wikipedia article "Gemstones".
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