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There are over 3,000 different
minerals, but only about 50 are commonly used as a
gemstones. Others are cut for collectors of the
unusual, but are often not suitable for wear because
they are too soft and easily scratched. In fact, the
number of minerals regarded as gemstones constantly
changes, as new sources and varieties are found and
fashions
change. Over 130 gem species, including some
exceptionally rare stones, are described in this
website, illustrating the very wide range of naturally
occurring gemstones
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Amber
is the fossilized resin of trees. Ambers are
golden orange in color. Amber contains insects
(flies, frogs, lizards), moss, lichen or pine
needles that were trapped millions of years ago
when the resin was still... |
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Aquamarine
comes in the color of sky blue and dark blue.
Aquamarine is often dichroic, appearing
colorless or blue while it is viewed from
different angles. The colour of aquamarine,
however, is usually more even than that of .... |
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Sapphire
All gem quality corondum that is not red is
called sapphire, yet most sapphires are
assosiated with colour blue. Variation in color
of sapphire is due to the content of iron and
titanium impurities in them..... |
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Emerald is a green colored gemstone.
Emerald gets its glossy green color from the
presence of chromium and vanadium. The name
emerald comes from the Greek 'smaragdos' via the
Old French 'esmeralde', and really..... |
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Ruby
is considered the king of the gemstones. In the
fascinating world of gemstones, the ruby is the
undisputed ruler. Ruby is the name given to red,
gem quality corondum.
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Peridot has an olive or bottle green
color due to the presence of iron, and an oily
luster. It has high birefringence, so the
doubling of the back facets can easily be seen
in large peridots when.... |
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Cubic Zirconia
is a colourless gemstone which closely resembles diamond and oftenly
mistaken as diamond. The name probably comes from the Persian word 'zargun',
which means 'gold-coloured' |
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Garnet - By the term
'garnet', the specialist understands a group of
more than ten different gemstones of similar
chemical composition. It is true to say that red
is the colour most often encountered... |
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Amethyst
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Crystalline quartz in shades of purple, lilac,
or mauve is called amethyst. The amethyst is
extravagance in violet. For many thousands of
years, the most striking representative of the
quartz family |
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Turquoise
is one of the first gems to be mined. Turquoise has an intense color which
varies from sky blue to green, depending upon the amount of iron and copper
in it.
Being relatively soft, having a hardness of 6. |
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The name
diamond is
derived from the Greek word adamas which means
invincible. It was given in reference to
diamond’s great hardness. Diamond is the hardest
mineral on Earth |
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The name
coral
however comes from the Greek 'korallion', which
denotes the hard, calcareous skeleton of the
coral animals, or from 'kura-halos', for
'mermaid', as the fine branches... |
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Beautiful quartz,
the 'rock crystal' used in ancient times to make
crystal balls and bowls, is today more often
seen set in gold jewelry. |
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Pearls are organic gems.
Pearls are formed in shellfish especially oyesters. Long ago, pearls were
important financial assets....... |
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Topaz word
is derived from the Sanskrit word "tapas", meaning fire. The topaz has
been known for at least 2000 years and is one of
the gemstones which form the foundations of the
twelve gates to the Holy City of the New
Jerusalem |
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The name Jade
is derived from the Spanish 'piedra de ijada',
loin-stone, jade having been recognised by the
Amerindians as a remedy for kidney ailments. |
World's Largest Diamonds set in the Crown Jewels of
various nations. Read their mysterious stories and their Legends.
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NATURAL GEMSTONES
A natural gemstone is a mineral, stone, or
organic matter that can be cut and polished or otherwise
treated for use as jewelry or other ornament. A precious
gemstone has beauty, durability, and rarity, whereas a
semiprecious gemstone has only one or two of these
qualities. A gem is a gemstone that has
been cut and polished.
Diamond, corundum (ruby and
sapphire), beryl (emerald and aquamarine), topaz, and
opal are generally classed as precious stones. All other
gemstones are usually classed as semiprecious. |
Quick Links
World's largest diamonds
How
gemstones are formed
Gemstone cutters
List of
gemstones
Gem stone website
links |
ORGANIC
GEMSTONES
The four organic gemstone groups listed below
are highly prized for their beauty and rarity. However,
they are not as durable as gemstones from minerals:
Amber
(hardness: 2-2.5
Mohs)
A mixture of hydrocarbons
Specific gravity: 1.05-1.096 |
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Hard fossil resin or sap of ancient pine trees. Usually
amorphous (lacks crystalline structure). Sometimes
mined, sometimes gathered on seashores.
Varies from transparent to
semitransparent and generally from light yellow to dark
brown, but can be orange, red, whitish, greenish-brown,
blue, or violet. Can be dyed in any color. Takes a fine polish. Used mainly in
making beads or other ornaments.
Coral
(hardness: 3.5-4
Mohs)
Formed mainly of calcite (calcium carbonate) or
conchiolin, a horny organic substance
Specific gravity: 2.60-2.70
Each coral polyp, a tiny marine
animal that lives in enormous colonies, extracts calcium
carbonate from the sea and exudes it to build a
protective home around and above itself. Each generation
of polyps dies in its protective home and each
succeeding generation builds on top of its predecessor. Gem coral ranges from
semi translucent
to opaque and occurs in white, pink, orange, red, blue,
violet, golden, and black. The black and golden corals
are largely horny organic substances, not calcium
carbonate. The finest coral is used to make
figurines, cameos, carvings, and beads.
Jet
(hardness: 2.5-4
Mohs)
Carbon plus various hydrocarbon compounds
Specific gravity: 1.30-1.32
This compact velvet-black coal takes
a good polish and is often cut into beads, bracelets,
and a wide range of decorative and useful objects.
Pearl
(hardness: 2.5-4.5
Mohs)
Formed within a mollusk, such as an oyster, that
deposits a substance called nacre around an
irritant that entered the organism
Specific gravity: 2.71
Pearl-bearing mollusks are found in
both salt and fresh water. Salt-water pearls of gem
quality are usually preferred for jewelry; they are
produced almost entirely by the mollusk Pinctada.
Fresh-water pearls are produced by various clams and
mussels.
Natural pearls come in various shapes: round, pear,
drop, egg, and others. They also come in various colors,
such as white, cream, light rose, cream rose, black,
gray, bronze, blue, dark blue, blue green, red, purple,
yellow, and violet.
HOW GEMSTONES ARE FORMED Most gemstones are mineral
crystals that formed during one of three
rock making processes: igneous rocks,
metamorphic rocks and sedimentary rocks.
Gemstones that have a mineral origin are
found in rocks, or in gem gravels derived from
these rocks. Rocks themselves are made up of
one or more minerals, and may be divided into
three main types. The formation of these three
types -igneous, sedimentary, or metamorphic - is
a continuous process, best described in terms of
the rock cycle. Gem-quality minerals within
these rocks may be easily accessible at the
Earth's surface, or lie buried deep beneath it.
Others, separated from their host rock by
erosion, are carried by rivers to lakes or the
sea.
INCLUSIONS
Most minerals contain visible traces of their
genesis - perhaps tiny crystals of other
minerals that were caught up in the growth of
the larger host crystal, or formed
simultaneously as it grew, internal fractures
that have been partially healed during growth,
or traces of earlier growth stages, marked by
zoning. Gemologists use the word
inclusions to describe these and other
internal phenomena.
GEMOLOGY
Gemstones are
scientifically fascinating, too. Gemologists
make a complete study of each
stone,
both as it is found in rocks and after it has
been
cut and
polished.
That is why the species entries in this website
show the gem in its rough, natural state,
perhaps still embedded in the host rock (or
"matrix"), as well as after it has been cut,
polished, or
carved. Many entries also feature a
micro-photograph which reveals the internal
structure of the stone by magnifying it many
times. In this world within a world the
gemologist may turn detective, being able to
distinguish between two outwardly similar
gemstones, or between a natural gemstone and a
synthetic gemstones.
Meanings of gem
names
Gemstone meanings
Amethyst
The word "amethyst" is of Greek origin and is translated as- "amethystus"
meaning not drunken, or intoxicated ("-methystos" from "methyein" or
intoxicated, "methy" = wine).
Aquamarine
Aquamarine derives its' name from "sea water." According to some legends,
aquamarine is the treasure of mermaids, with the power to keep sailors safe.
Diamond
Comes from the Greek word, "adamus" which means unconquerable, utterly
unyielding in attitude or opinion in spite of all appeals, urgings etc.
Emerald
The name emerald is a derivative of an ancient Persian word, coming to us
through the corruption of the Latin `Smaragdus'. The history of the emerald is
as fascinating as it is voluminous. The ancients prized it as the symbol of
love, rebirth and eternal youth.
Garnet
Garnet derived its name from the French word ''grenat"
meaning Pomegranate and "granatus" meaning grain. So called from its resemblance
in color and shape to the grains or seeds of the pomegranate.
Opal
Greek word "opállios" meaning gem and a source
akin to Sanskrit "upala" precious stone.
Pearl
Peridot
The name Peridot comes from the Arabic word "faridat," meaning gem. Ancient
Egyptians called them the "gem of the sun," because of their dazzling brilliance
when seen in the desert sun.
Ruby
The word Ruby comes from the Latin "ruber," meaning red..It has been said that
the Ruby's red glow comes from an internal flame that cannot be extinguished
Sapphire
Sapphire was named after the Greek word "sapphirus", meaning blue. The striking
deep blue of a quality sapphire is reminiscent of a cloudless night sky.
Topaz
The name topaz was derived from the Island of Topazos in the Red Sea, which
probably refers to Zeberged, ancient source for peridot. But it is more likely
that the name derives from the Sanskrit word "tapas" meaning fire.
Turquoise
Turquoise was so named because it was initially brought to Europe by way of
Turkey, this stone is one of the first gems to be used in jewelry.
Turquoise was considered by ancients to be a sacred stone, protective against
all manners of evil and ill health. This beautiful gemstone is mined in
Iran and the southwestern United States. A gift of Turquoise represents
friendship and luck. The Persian word for turquoise is "ferozah" or "firozah",
which means victorious.
BIRTHSTONES
Early civilization as far back as the
Assyrians (1400 BC) invested rare and beautiful
gemstones with magical properties. Some minerals were
thought to contain a force or possess certain values and
powers. For instance, amethyst was said to prevent
intoxication. Tradition associates a gem with each sign
of the zodiac based on a color system. Color was thought
to unleash the power attributed to the birthstone. In
time, birthstones became associated with calendar months
rather than the zodiac. And people began to select
birthstones in colors other than the original.
Birthstone List
List of birthstones for each month
Zodiac Birthstones, Astrology, Birthstone signs
Birthstone Zodiac signs are the
astrological version of the monthly birthstones that
symbolize the month of birth. The Birthstone Zodiac
signs use the twelve zodiac signs instead of the twelve
calendar months. Every sign of the zodiac is ruled by
one of the planets in the Solar system and each planet
rules over specific gemstones according to their color.
The following birthstone chart, or birthstone list,
contain details of each sign and the various gem stones
that are the closest to vibrate to their particular
sign. The signs of the Zodiac are used to cast
horoscopes from astrological calculations which are used
as a guide to personality, relationships and business
affairs. The twelve Zodiac signs represent the "houses"
or divisions into which the heavens are charted by the
astrologer. The Zodiac signs represent the placement in
the sky where the sun was during the time of birth. The
twelve signs of the Zodiac are Aries, Taurus, Gemini,
Cancer, Leo, Virgo, Libra, Scorpio, Sagittarius,
Capricorn, Aquarius and Pisces. Each sign of the Zodiac
influences people who were born between certain dates.
Life predictions are upon the position of the planets in
the "twelve houses " at the moment of the birth. The
signs of the Zodiac change on, or about, the 22nd of
every month. Every sign of the zodiac is ruled by one of
the planets in the Solar system and each planet rules
over specific gemstones according to their color. The
energies associated with each planet are affected by a
classical element to which the sign belongs to either
fire, earth, air, or water. The gemstones assigned to
each of the Zodiac signs are believed to influence both
positive and negative personality traits and
characteristics. Click one of the following links to
find out about the personality and characteristics of
each Zodiac sign and the influence of their
corresponding birthstones:
Birthstone list - List of birthstones
for each month
SYNTHETIC GEMSTONES
Synthetic gemstones are made in
laboratories or factories, not in rocks. They have
virtually the same chemical composition and crystal
structure as natural gemstones, so their optical and
physical properties are very similar. However, they can
usually be identified by the differences in their
inclusions. Many gems have been synthesized in the
laboratory, but only a few are produced commercially-
generally for industrial and scientific purposes.
PRECIOUS
GEMSTONES
SEMI PRECIOUS
GEMSTONES
Natural Gemstones vs. Synthetic Gemstones
Author: Debra Hamer
What is a synthetic gemstone? A
synthetic gem is created in a laboratory under
controlled conditions. The gem is grown from a natural
gemstone “seed”. By controlling the environment in which
the gem is grown, impurities and inclusions can be
avoided which occur in natural gemstones. The created
stones have perfect color and clarity which is so highly
desired. Most natural gemstones have imperfections due
to uncontrolled growing conditions in nature. Synthetic
stones will have the same chemical, physical, and
optical properties of their natural counterparts without
the imperfections.
A good analogy for synthetic gemstone
creation is growing roses. Roses grown in a hot house
where their growing environment is controlled will be
closer to perfection than roses that are grown in your
backyard. They're both roses, but the backyard rose will
most likely be flawed or imperfect due to disease,
insects, and other environmental impacts. Not so with
the hot house rose because of the controlled conditions.
Don't confuse simulant gemstones with
synthetic gemstones. Simulants can be made up of any
substance, like glass. They are made to simulate a
particular gemstone, but they do not have the same
chemical, physical, and optical properties of the
natural gemstone like the synthetic gemstone. Some
examples of simulants are cubic zirconia, moissanite,
and yttrium aluminum garnet which are diamond simulants.
The most popular gemstones that
synthetics have been created for are emeralds,
sapphires, rubies and alexandrites. I'm sure you have
seen jewelry with synthetic stones, also known as
“created” gemstones in your local retail jewelry store.
They are easier to obtain and less costly than natural
gemstones. Synthetics have made it more affordable for
people to own nice jewelry and many prefer the flawless
created stones compared to the natural stones. You can
usually spot a “created” stone because it's just too
perfect in color and clarity. A natural stone,
especially in rubies, sapphires, and emeralds, which is
perfect in color and clarity, is scarce and the cost is
beyond most people's means.
Should you buy a synthetic gemstone
or jewelry with created stones over the natural gemstone
choices? I would recommend going with your own personal
preference. If you want a piece of jewelry with a
flawless, perfect gem, then go with the synthetic
gemstone. Also, if cost is a deciding factor. As a
collector/investor my preference would be for the
natural gemstone. It's value and appreciation factor
will be much greater, flawed or not.
It's interesting that there are some
gemstones man has not been able to synthesize in a
laboratory. One example is the garnet family of gems.
They have not been able to unlock garnet's secrets to
create it in a lab.
How do I know if the gemstone is
natural, synthetic (created), or a simulant? If you
can't tell by your own examination...ask! A reputable
dealer or jeweler will be honest about the origins of
the stone. If they don't know or won't say, then don't
buy!
Another interesting fact about
gemstones that is not common knowledge to the public is
that the majority of gems on the market have been
treated to create or enhance their color and clarity.
There are many different treatments used today. Heat
treatment is the most common and widely used. I have
written another article specifically regarding gemstone
treatments.
IMITATION
Imitation gems have the appearance of their natural
counterparts, but their physical properties are different. They are made to
deceive. Man-made materials, such as glass and synthetic spinel, have been
used to imitate many different gems, but natural stones can also be modified
to resemble more valuable gems. It is possible to enhance authentic
gemstones by hiding cracks and flaws, or by heat-treating or irradiating to
improve their color. Imitation gemstones merely imitate the color or look of
a natural stone. They can be made out of anything. A cubic zirconia is an
IMITATION diamond, for example. A blue piece of glass could be an imitation
sapphire. A variety of blue synthetic forsterite is an excellent imitation
for tanzanite, while chemically, it's composition is much closer to the
yellowish green peridot. Another classic example is the "alexandrite" set in
many jewelry pieces is actually a variety of vanadium colored synthetic
sapphire.
GEMSTONE PROPERTIES
COLOR
PLEOCHROIC
GEMS
REFRACTIVE
INDEX
BIREFRINGENCE
FLOUROSCENCE
ALLOCHROMATIC GEMS
IDIOGHROMATIC GEMS
PARTLY-COLOURED GEMS
INTERFERENCE
LUSTRE
HARDNESS
SCALES OF HARDNESS
SPECIFIC GRAVITY
CLEAVAGE AND FRACTURE
TENACITY & TOUGHNESS
MAGNETISM & ELECTRICITY
THERMAL CONDUCTIVITY
CRYSTAL SYSTEMS
CHEMICAL PROPERTIES
 
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