Tuesday, April 28, 2015
Saturday, April 25, 2015
Jade / Mrgaj Gemstone
In
Urdu, Jade is called Margaj. For many centuries in ancient days, Jade was
considered as the same type of gem. In the year 1863, Jade was accepted to have
two forms - Jadeite and Nephrite. Both are used in jewellery. Jade substitute
started spreading all countries from Europe .
In ancient, Jade was used to make tools. In America , Jade is used for treatment
of kidneys. Hence, this substitute is costlier then gold.
This
sub-stone has the appearance as of emerald. Jade of green color is costlier
then emerald. Good quality of Jade is
translucent. Jade is available in many colors. Like, light shades of yellow,
pink, blue, and black. Some of them have a mixture of all these colors.
Importance of Jade in China :
Jade
is used in every house of China .
The idol of goddess Kuan Yin of China
is made of this sub-stone. She is the goddess of kindness and compassion. She
is the mentor of maternity and young children. Idol made of Jade saves a person
from negativity in a magical way. It purifies the atmosphere of house and saves
from evil spirit.
Jade Properties:
Jade
is one of those substitutes which don not cause any sort of problem to the
person wearing the gem nor they allow any negative energy to flow in a person’s
body. So, anyone can wear this gemstone. This sub-stone is known as the symbol
of love. In China ,
butterfly made of this gemstone is worn to attract the person you love. It is
full of latent power and beauty.
This
substitute is auspicious for people who want to have bright fortune. It increases
balance, peace and wisdom in a person. It is a powerful and uncommon gemstone.
It raises the consciousness of an individual. In ancient days, it was worn to
protect oneself from snake bite. Jade is also worn for long and peaceful life.
In
modern time, it is worn to make a persons dream come true. It gives person
courage to fulfill his dream and helps a person to come out of deception. It is
believed that keeping this substitute under pillow or bed keep the negative
feelings away from entering in dreams.
Miraculous Properties of
Jade:
Jade
is also used for medicinal purpose. It brings relief to people suffering from
epilepsy. It cures the problems related to kidney and stops the diseases caused
to kidney. This gem is used for healing problems related to skin. It removes
the deficiency of calcium. It purifies blood and saves from diseases caused to
eyes.
Jade
is good for the immune system. It gives relief from problems related to hairs.
It helps in proper functioning of digestive system. People having problem of
constipation should wear this sub-stone.
Who should wear Jade?
Everyone
can wear Jade. A person should wear this sub-stone if mercury is the lord of
the auspicious house but is in weak position in horoscope. It is also worn as
substitute of emerald.
Thursday, April 23, 2015
How to Identify Real Pearls
Four Methods
Thinking of buying pearl
jewelry? A few simple tests can help you determine whether your pearl item is a
fake or real, cultured pearl or real pearl, plastic or real, man-made pearl or real pearl? Learn how to
look and feel for the signs of a real pearl today and you'll never need to
worry about falling for imitations again.
Method 1 of 4: Touch Tests
Rub the pearls against your
front teeth. Hold one or two pearls between your thumb and forefinger and press
them gently into the biting edge of your front teeth. Rub them against your
teeth with a side-to-side motion. A real pearl will usually have a slightly
rough or gritty texture from tiny scale-like imperfections in its outer layers
of nacre. Fake pearls made from glass or plastic will usually almost perfectly
smooth. You may want to brush your teeth before attempting this test to make
sure they're clean. Food residue from a recent meal can give false results.
Step 2
Rub the pearls against each
other. Hold a few pearls in your fingers and gently rub them against each
other. Feel for the slight sensation of friction. Real pearls will usually
generate a little friction when they rub against each other because their outer
layers of nacre are not perfectly smooth.[2] Fake pearls, on the other hand,
often have smooth coatings and will usually glide past each other when rubbed
together.
Take a close look at your
hands after this test. When two pearls rub against each other, their outer
layers often erode a small amount. If you notice a fine, powdery, white residue
after rubbing your pearls, this is probably powdered nacre — a sign that the
pearls are real.
Step 3
Check whether the pearls are
perfectly round. Because they're products of nature, every real pearl is
slightly different, just like snowflakes or fingerprints. Most pearls won't be
perfect spheres — they'll usually be slightly oblong or have minor defects. If
your pearls look perfectly round to you, there's a good chance they're
artificial.
It is possible for real
pearls to be perfectly round. However, examples of these are very rare and
usually fetch a high price.
Not sure whether a pearl is
perfectly round or not? Try carefully rolling it on a flat surface. Imperfect
pearls won't consistently roll in a straight line.
Step 4
Feel for coolness to the
touch. For this test, you'll need a few pearls that have been sitting out — not
ones you've been wearing. Hold the pearls in your hand and concentrate on the
way they feel against your skin. Real pearls should feel noticeably cool for a
few seconds before they warm up. The feeling is similar to what you'd get from
stepping barefoot onto a marble floor.
Plastic pearls, on the other
hand, will be about room temperature and will warm up more quickly.
Note: Good-quality fake glass
pearls may still give the "cool" sensation. Verify your results with
other tests if this is the first one you've attempted.
Step 5
Feel the weight of the pearl
in your hand. Carefully bounce one or two pearls in your hand to get an idea of
how much they weigh. Most real pearls feel somewhat heavy for their size. On
the other hand, fakes (especially plastic pearls) will have a light,
insubstantial feel.
For obvious reasons, this
test isn't perfect — judging the weight of a few small pearls can be tricky.
For best results, you may want to compare your pearls with a set you know are
real or fake. Always verify with another test no matter how sure you are of a
pearl's weight.
Method 2 of 4: Visual Tests
Step 6
Look for minor imperfections.
As noted above, real pearls are only rarely "perfect". Usually,
they'll have small blemishes or irregularities in their shape. Their outer
nacre layer may also reflect light differently on different parts of the pearl.
Imitation pearls are almost always "too perfect" — they look perfectly
spherical; they have the same amount of luster on every part of the surface,
and show no indents or imperfections.
While perfectly round real
pearls are rare but possible, a necklace will almost never be made only from
these types of pearls. A necklace made from pearls that all seem to be exactly
the same smooth, round shape is almost certainly a fake.
Step 7
Check for a sharp, healthy
luster. Luster is a way that jewelers describe the type of light reflected from
a precious stone. A pearl's luster is part of what makes it so beautiful.
Good-quality pearls should have a bright, clear luster that makes them shine
when light hits them. If you look closely, you should be able to see your own
reflection on the pearl's surface.
One problem with this test is
that low-quality real pearls (which generally have a dull, "chalky"
luster) can look similar to fake pearls. Check your results with a few of the
other tests in this article.
Step 8
Check for an overtone.
Good-quality pearls are often prized for their overtones — the subtle color
that is visible on their outer surface when light hits them. Fake pearls will
usually not have this overtone effect, which is tricky to duplicate. Thus, if
your pearl seems very slightly shaded with color when a light hit is, there is
a good chance its real. Rose and ivory are two of the most desired overtones
for white pearls, though a wide variety of colors are possible, especially for
dark pearls.
Since some real pearls don't
have a visible overtone, not seeing an overtone on your pearl isn't necessarily
a sure sign that it's fake.
Step 9
Look for clues around the
drill hole. Pearls on a strand or necklace will usually have holes drilled in
them for the string to pass through. Examining this hole carefully can help you
tell whether your pearl is real or not. Specific things you'll want to look for
include:
Well-defined edges to the
hole:
Real pearls usually have
drill holes with sharp edges (like a hollow cylinder). Fakes often have rough
or rounded edges. However, old and well-worn real pearls may also have rounded
edges to their holes. Fake pearls may also bow outward at the surface of the
pearl, rather than being perfectly cylindrical.
Chipped paint or coating
around the hole:
As fake pearls rub against
each other with repeated use, their artificial coating can wear away around the
holes. You may be able to see slivers of glass or plastic underneath. This is a
sure sign of a fake.
Step 10
Look in the hole for a line
between the nacre and nucleus. A real pearl almost always has a clear outer
nacre layer, while fake pearls have thin layers of artificial nacre or lack
them entirely. If your pearl has a drill hole, you can check for nacre by
peering in with a magnifying glass. Real pearls will usually (but not always)
have a noticeable line that separates the nacre from the nucleus (the inside
part of the pearl).
Method 3 of 4: Advanced
Tests
Step 11
Check for "scaly"
surface patterning with a microscope. You can use a 30x jeweler's loupe, but
microscopes with 64-power magnification or more work best for this. The
surfaces of real pearls have a maze-like, scaled pattern. This patterning looks
a little like a topographical map. It's this microscopic scaling that gives
real pearls their "gritty" texture.
By contrast, fake pearls will
often have a surface covered with grainy, fairly regular bumps (a little like
the cratered surface of the moon).
Step 12
Compare your pearls to
certified real pearls. All of the tests above are easier if you have some
pearls that you know are real for comparison purposes. Try contacting a jeweler
about the possibility of comparing your pearls to a set of ones that are
certified real. Alternatively, borrow a friend or relative's real pearls to
make your comparisons.
Use common sense about the
sorts of tests you do with the certified real pearls. For example, you won't
want to try the tooth test or the friction test with someone else's precious
stones.
Step 13
Get your pearls appraised by
an expert. If you are having a hard time determining your pearl’s authenticity,
you can always take your pearl to a reputable jeweler or gemologist. These
professionals have the tools, training, and expert eyes to tell whether your
pearl is real (and, if it is real, how high its quality is). However, these
options often don't come cheap — a basic appraisal can easily cost more than
$100.
Step 14
Try ordering an X-radiograph
test. This test, which an expert may do to determine whether your pearls are
real or not, uses an X-ray machine. Real pearls will show up as a semitransparent
grey color on the X-ray. Fakes will be solid white on the negative and solid black
on the positive print.
Step 15
Try ordering a refractometer
test. This advanced test measures how much light passes through the pearl to
determine its authenticity. Pearls usually have a refractometer reading (called
a "refractive index") of between 1.530 and 1.685. The difference
between these two values (0.155) is called the pearl's birefringence, which
affects the way the pearl looks in the light. These qualities tell an expert
that the pearl is most likely a real one.
Method 4 of 4: What to Avoid
Step 16
Beware of using just one test
to verify pearls. This bears repeating: any single one of the tests above can
sometimes produce false results. To be sure of your results, perform many
different tests.
As just one example of how
isolated tests can be misleading, one source found that real pearls that have
been specially polished can feel very smooth in the tooth and friction tests.
Step 17
Avoid the "burn"
test. Some sources may recommend holding pearls in an open flame to determine
whether they are fake or not. According to this rumor, fake pearls will burn or
melt, while real pearls will be unaffected. The truth is more complicated.
While most fake pearls will be damaged by fire, so will some real ones. Real
pearls that have been processed with an artificial outer coating are especially
vulnerable to flame and can suffer from blemishes, deformed drill holes, and
ruined luster after just a few seconds in a flame.
In addition, it's worth
noting that pearls conduct heat well and can become very hot when heated over
an open flame. If you do attempt this test, take all necessary precautions to
avoid bad burns.
Step 18
Don't fall for imitation
pearls sold with exotic names. If a seller is trying to sell you on a pearl's
name rather than its physical qualities, you may be getting ripped off. For
example, "Mallorca" (or "Majorca") pearls, which are named
after the exotic Mediterranean island
of Mallorca but are
entirely man-made, are sometimes sold to unsuspecting costumers.
Step 19
Don't ignore common sense
instincts about a pearl's price. The price of a real pearl will vary greatly
based on its size, shape, overtone, and other features. However, they will
never be outright cheap. For instance, a necklace made from freshwater pearls
(the cheapest variety of real pearls) can easily retail for several hundred
dollars. If a seller is giving you a deal on a set of real pearls that seems
too good to be true, it probably is.
Wednesday, April 15, 2015
Popular Gemstone
ALEXANDRITE
|
Alexandrite
is a variety of chrysoberyl that displays a colour change depending on light
conditions and the angle it is view from (pleochroism).The ideal colour
change would be fine emerald green to fine purplish red, but this is rare and
expensive. Alexandrite was discovered in the Ural Mountains of Russia in the
1830's, and named after tsaravitch Alexander, the future tsar. That area was
mined for over 60 years and still today Russian Alexandrite is considered the
best quality. Today, small quantities of Alexandrite are mined in
Colour:Green in daylight and red-violet in incandescent light. Hardness: 8.5 |
AMBER
|
Amber is the
fossilized resin from ancient forests. In ancient times the resin dripped and
oozed down trees, filling fissures and trapping debris such as seeds, leaves,
feathers and insects. The resin then became buried and fossilized through a
natural polymerisation creating amber. The two main sources of amber in
today's market are the Baltic states and the
Hardness: 2.5-3 |
AMETHYST
|
Amethyst is
a transparent purple quartz. Origin of name from the Greek -amethystos-
"not drunken". Amethyst was considered to be a strong antidote
against drunkenness. Greek legend tells the story of a maiden Amethystos who
was pursued a drunken god called Dionysus. She prayed to the goddess Artemis
to remain chaste. The goddess granted her prayer, transforming her into a
white stone. Filled with remorse Dionysus cried tears of wine over the stone
turning it purple.
Different localities can produce a unique amethyst to that particular region or even to that particular mine. It is mined in Colour:the colour range varies from pale lilac to deep purple. Hardness: 7 |
AQUAMARINE
|
Aquamarine
belongs to the gemstone family of Beryls. Origin of name Latin
"aqua"meaning water and "mar"sea. Legend has it that
Mermaids tails were made of aquamarine. Aquamarine is usually free of
inclusions and possesses a superior brilliance. The more intense the colour
of an Aquamarine, the higher its value.The principle supply of aquamarine
stones comes from Brazil, Russia, Afghanistan, India and Pakistan
Colour:pale blue to light greenish Hardness: 7.5-8 |
BLOODSTONE/ HELIOTROPE
|
Bloodstone
or heliotrope, is a form of Chalcedony, a cryptocrystalline quartz.
Bloodstone is green jasper with red inclusions. The red is sometimes caused
by iron oxide or red jasper. Origin of name: From the red spots looking like
spots of blood. It is usually cut "en cabochon" (that is shaped and
polished usually with a flat bottom and a convex top) or into beads, it is
used as a sealstone and in signet rings. Bloodstone is found in
Colour: green with red inclusions Hardness: 7 |
APATITE
|
Apatite is
part of the phosphate mineral group. Origin of name: From Greek apate meaning
deceit alluding to its similarity to other more valuable minerals such as
olivine, peridot and beryl. Apatite is found in different worldwide locations
like:
Colour: varies from being transparent to opaque, with colours ranging from yellow, green, blue, violet and colourless. Hardness: 5 N.B.This stone is very sensitive to heat and care needs to be taken. |
CITRINE
|
Citrine is a
form of quartz with ferric iron impurities and is rarely found naturally.
Origin of name from the French word "citron" meaning lemon. Also
called citrine quartz. Most commercial citrine is in fact heat treated
amethyst or smoky quartz.
Colour: the different shades range from yellow, gold, orange brown shades of transparent quartz. Hardness:7 N.B. Citrine and Amethyst are the exact same minerals, the only difference is the level of oxidation of the iron contained in the mineral. As this can be done artificially by heat or irradiation a large majority of Citrine sold today is heat treated amethyst. There are currently no scientific ways to determine if Citrine was changed artificially. |
CORAL
|
Precious
coral or red coral is the common name given to Corallium rubrum. The hard
skeleton of red coral branches is made up of mostly calcium carbonate and is
durable and intensely coloured. Coral can be polished to a glassy shine.
Usually deep water corals have light colour and shallow water corals have
deep colour. Coral jewellery has been found in ancient Egyptian and
prehistoric European burials and continues to be made to the present day. Due
to its softness and opacity, coral is usually cut as a cabochon or used to
make beads.
Hardness:3.5 |
CUBIC ZIRCONIA
|
Cubic
zirconia or CZ is a synthetic variant of the mineral baddeleyite which is
extremely rare in nature. It is the oxide of the metallic element zirconium,
zirconium dioxide. It was first used in the Russian space program to serve as
a window to photograph through, it was not used in jewellery until 1969 when
somebody decided to facet the material. It is often used as a diamond
simulant. Cubic zirconia should not be confused with zircon, which is a rare
naturally occurring gemstone.
Colour: By adding other minerals in the creative process CZ's can come in any colour as well as the colourless variety. Hardness:8.25-8.75 N.B. Key features that distinguish CZ from diamond: Cubic zirconias have more dispersion than diamonds so show more fire. A CZ has a Mohs rating of 8.5-9 and Diamonds have a rating of 10. A CZ is 1.7 times heavier than a diamond of equivalent size. CZs are optically flawless whereas the majority of diamonds have inclusions or flaws CZ has a refractive index of 2.176, compared to a diamond's 2.417. CZ can be made in most cases entirely colourless: equivalent to a perfect "D" on diamond's colour grading scale but it is rare to find diamonds are truly colourless. CZs are thermal insulators whilst diamonds are among the most efficient thermal conductors. |
DIAMOND
|
Diamonds are
a form of carbon. Origin of name: From Greek for invincible. Please click here to go to our more comprehensive
section on Diamonds.
Colour: it is rare to find diamonds are truly colourless. Hardness: 10.00 |
COLOURED DIAMONDS
|
Diamonds
come in all colours but these natural Fancy Colour Diamonds are rare and can
be very expensive. One out of 10,000 normal diamonds is a fancy colour diamond.
The colour of a fancy coloured diamond is measured differently to a normal
diamonds. The grading scale is based on the intensity of the colour. The GIA
fancy colour grading scale is: Faint, Very Light, Light, Fancy Light, Fancy,
Fancy Intense, Fancy Vivid, Fancy Deep and Fancy Dark.
|
EMERALD |
Emerald is a
valuable Beryl that owes its colour to chromium or vanadium, which make it
the bright green. Origin of name emerald is said to be a Sanskrit word
meaning green (Sanskrit is a classical language of
Colour: Emeralds come in many shades of green and bluish green. Hardness: 7.5-8 N.B. Many emeralds are treated to hide surface-reaching breaks and improve transparency. |
FIRE OPAL
|
Fire opal is
a bright orange variety of opal.
It is primarily found in Colour:Fire opals are transparent to translucent opals with warm body colors yellow, orange, orange-yellow or red. Hardness:5.5- 6.5 |
GARNET
|
Garnets are
nesosilicates. 0rigin of name: from ancient Greeks as colour reminded them of
the pomegranate seed or granatum. Garnets do not show cleavage (the tendency
of crystalline materials to split along definite planes, creating smooth
surfaces) so when they fracture under stress, sharp irregular pieces are
formed. Because the chemical composition of garnet varies, the atomic bonds
in some species are stronger than in others. The harder species are often
used for abrasive purposes. It is found in the regions of
Colour: virtually all colours Hardness:6-7.5 |
IOLITE
|
Iolite is a
blue silicate mineral that occurs as crystals or grains in igneous rocks,
Origin of name: from the Greek ios, which means violet. Iolite changes
colours (pleochism) depending upon which angle it is viewed from and the gems
are cut to take advantage of that. It is found in
Colour: Transparent, violet-blue, light blue, blue, rich blue-violet stone Hardness 7.5 |
IVORY
|
Ivory is a
hard, white, opaque substance that is the bulk of the teeth and tusks of
animals such as the elephant, hippopotamus, walrus, mammoth and narwhal.
Ivory had been used for thousands of years for tools, implements and weapons
and for carving and jewellery. The 1990 Convention on International Trade in Endangered
Species (CITES) put
a ban on international ivory sales to lessen the threat to endangered species
by poaching. A species of hard nut sometimes called vegetable ivory or
"tagua" is gaining popularity as a replacement for ivory.
|
JADE
|
The term
"jade"refers to two different, yet similar semi-precious
metamorphic mineral gemstones, Jadeite and Nephrite. Nephrite and jadeite are
resistance to breakage and chipping and due to their toughness they made a
superior weapons and tools for early man. Not until the 19th century that a
French mineralogist determined that "jade" was in fact two
different materials. Nephrite is usually only green and creamy white, while
jadeite can have the full range of jades colours. Jade is mined in the
regions of
Hardness:6 |
JASPER
|
Jasper is
microcrystalline quartz and is made from very small grains, it is a
semi-translucent to opaque. Jasper has been used for thousands of years as tools
and weapons during prehistoric times and for ornaments and jewellery later.
Origin of name from the Greek iaspis. Jasper is commonly found in the regions
of
Colour: dark green,yellow, brown, green, yellow, red and white. Hardness: 6.5 to 7.5 |
JET
|
Jet is a
hard gem variety of Lignite. Jet is a type of brown coal, a fossilised wood
of an ancient tree similar to our present monkey puzzle trees and cypress
trees. These trees flourished in the Jurassic period when the trees died and
fell they were eventually washed into rivers and seas to lie at the bottom
for millions of years. All the other sediment built up causing great
pressure, which flattened the wood and together with chemical changes altered
the wood to jet. Jet has been used in Jewellery since ancient times and Queen
|
LAPIS LAZULI
|
Lapis lazuli
is an opaque to translucent precious gemstone composed mainly of lazurite and
calcite. Origin of name from the Persian "lazhward", which was the
name of a place in modern Turkestan known for its deposits of lapis lazuli
(“stone of lazhward”). The finest colour is intense blue, lightly dusted with
small flecks of golden pyrite. Polished Lapis can be made into jewellery. In
the past it was also ground and processed to make the pigment Ultramarine for
tempera paint and oil paint.
Colour: Deep azure blue to light blue, bluish green Hardness: 5.5-6 |
LARIMAR
|
Larimar is a
semi-precious blue variety of pectolite, Sodium Calcium
Silicate Hydroxide. It was discovered in the
Colour: pale blue to sky blue Hardness: 5 |
MARCASITE
|
In
jewellery, iron pyrite used as gem is improperly termed "marcasite"
Origin of name from Arabic or Moorish for pyrite. Pyrite and Marcasite share
the same exact chemical make up; however they both differ in their interior
structure." Marcasite" is frequently found in inexpensive silver
jewellery and watches. It was fashionable and popular in Victorian and other
times where it was often used to imitate diamonds. In better quality
jewellery it is hand-set with grains or beads of metal from the setting being
pushed over the edges of the stones." Marcasite" occurs world-wide
and is easily found in the chalk near
Colour: metallic Hardness:6-6.5 |
MOISSANITE
|
Naturally
occurring Moissanite was discovered in 1905 by Dr. F.H. Moissan, a French
chemist and Nobel Prize winner and was named after him. Natural moissanite is
very rare and is limited to iron-nickel meteorites. Virtually all of the
moissanite sold in the world is synthetic. Synthetic moissanite is also known
as silicon carbide after its chemistry (in industry moissanite is known as
the man-made abrasive Carborundum). Moissanite is used as a diamond
substitute as it is transparent and hard with a slightly higher refractive
index than diamond. Moissanite jewels are cut to minimize their double
refraction or birefringent effects. It is lighter and much more resistant to
heat. This results in a stone of higher lustre, sharper facets and good
resilience. Moissanite remains undamaged by temperatures used to melt gold.
Colour:rarely clear to shades of very pale green. Hardness:9.5 |
MOONSTONE
|
Moonstone is
the best known gem variety of orthoclase feldspar. It is usually polished as
a cabochon. Its importance as a gemstone arises because of adularescence, a
floating light effect and sheen, compared to the light of the moon. This
phenomena results from alternating layers of two kinds of feldspar,which
cause light to scatter. Moonstone specimens commonly exhibit chatoyancy (a
mobile, wavering striped reflection), and sometimes display a strong cat's
eye.
Colour: most desirable colour of moonstone is blue, but it also occurs in grey, white, pink, green and brown. Hardness: 6 to 6.5 |
MYSTIC TOPAZ
|
Mystic topaz
is a treated clear topaz, it is not found naturally. To create mystic topaz,
natural, colourless topaz is coated with a thin layer of titanium. The
coating is only microns thick and is applied to the stones pavilion, the
underside angled portion that typically forms the bulk of the gem. The
specialized coating alters the stones natural refraction, creating rainbow
colours, predominantly blues, greens, yellows, and small bursts of red
shades.
N.B. this stone should be treated with care |
Onyx ia a
chalcedony that occurs in bands of different colours. Onyx refers to a black
and white banded variety of Agate and brown varieties are named Sardonyx. It
is composed of relatively straight, parallel layers of different colours.
This structure lends itself to cameo making.
It is usually cut into cabochon, or into beads, and is also used for intaglios and cameos. Some onyx is natural but much is produced by the staining of agate. It is available in the regions of Hardness: 7 |
|
Opal is a
type of quartz. Origin of name: from Sanskrit (Sanskrit is a classical Indian
language) upala = precious stone. They are luminous and iridescent with
inclusions of many colours. Opals show a play-of-colour (a shifting of
spectral colours)Opals are found in the regions of Mexico, Brazil, USA,
Japan, Honduras, Kenya, Czechoslovakia, Peru, Canada but by far Australia is
the main source of opals, almost ninety-five per cent of all fine opals come
from the dry and remote outback deserts.
Colour: White, black, red, orange, most of the full spectrum, colourless, iridescent. Very infrequently of a singular colour. Hardness: 5.5- 6.5 |
|
|
Colour: white or cream, but the colour can vary according to the natural colour of the nacre in the various species of mollusc used. Can also be black or various pastel shades. Pearls (especially freshwater pearls) can be dyed yellow, green, blue, brown, pink, purple, or black Hardness: 3.5 to 4.0 N.B.To test if a pearl is natural, rub across your across the edge of your teeth; real pearl feels rough, simulated feel smooth. |
PERIDOT |
Is the gem
quality variety of the mineral olivine. Origin of name either the Arabic word
faridat meaning "gem" or the French word peritot meaning
"unclear". Peridot is one of the few gem stones that come in only
one colour. The depth of green depends on how much iron is contained in the
crystal structure. It is found in the
Colour: varies from yellow-green to olive to brownish green. Hardness: 6.5 - 7 |
QUARTZ
|
Quartz is a
crystalline rock or mineral composed of silicon dioxide. Quartz is the second
most common mineral in the Earth's continental crust and found in all types
of geological environment. There are 49 variety's, a number of which are
gemstones, some of which are very beautiful and very rare. Origin of name
from Saxon word Querkluftertz = cross-vein ore.
Colour: colourless, white, gray, yellow to brown to black, violet, pink Hardness: 7 |
RUBY |
Ruby is the
red variety of the mineral called Corundum which is composed of aluminium
oxide (any other colour of corundrum is a sapphire, see below). The red
colour is caused mainly by chromium and titanium. It is natural for rubies to
have imperfections in them, including colour impurities and inclusions of
rutile needles known as "silk. Origin of name comes from ruber, Latin
for red. Some rubies show a 3-point or 6-point star or asterism. These rubies
are cut into cabochons to display this effect. Natural occurring rubies are
very rare and extremely rare in large sizes over 3 carats. They can be found
in many regions around the world from
Colour: pinkish red or deep, rich red colour Hardness: 9 N.B. Almost all rubies today are treated in some form (of which heat treatment is the most common practice) and rubies which are completely untreated and still of excellent quality command a large premium. Improvements used include colour alteration, improving transparency by dissolving rutile inclusions, healing of fractures (cracks) or even completely filling them. |
SAPPHIRE
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Sapphire is
any colour of the mineral corundum other than red, those are called ruby,
(see above) corundum is composed of aluminium oxide. Sapphires tend to be
translucent or transparent and have high amounts of refraction. The most
desirable sapphires are generally those with an intense blue colour with
plenty of sparkle and life. Various shades of blue result from titanium and
iron substitutions in the aluminium oxide crystal lattice. Some sapphires
show a 3-point or 6-point star or asterism. These sapphires are cut into
cabochons to display this effect. They can be found in
Colour: Shades of blue. Hardness: 9 |
COLOURED SAPPHIRES
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Sapphires
are mainly known for their shades of blues, but they come in an assortment of
colours.
Colour: all colours across the spectrum including white and black. Hardness: 9 N.B. It should be noted that many Sapphires can be treated to enhance or change their colour. They are heated or irradiated to produce stronger colours such as greens, yellows or even blues. While the colour of Sapphires can be changed by intense heat and radiation, it is stable for daily wear jewellery. |
SHELLS
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Shells are
organic minerals composed of calcium carbonate . Throughout the history
shells of many types and from many different kinds of animals have been
popular as human adornments. They are often used whole and drilled so that
they can be threaded. The intricate design and varying colour patterns of
shells is mainly dependent on the diet of the animal the shell covers. Mother
of pearl or nacre is created by molluscs such as oysters and abalones
secreting a substances that consist of calcium carbonate. Nacre is
continually deposited onto the inner surface of the animal's shell creating
the iridescent nacreous layer or mother of pearl. This is done both as a
means to thicken, strengthen and smooth the inner surface of the shell.
Mother of pearl has been used as decoration from buttons to inlays in
furniture, jewellery and much more for thousands of years. Mother of Pearl
can be found in many regions including
Colour: Hardness: |
NATURAL SPINEL
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Spinels are
composed of magnesium aluminium oxide. Most Spinel is formed due to intense
heat from volcanic activity or hydrothermal underwater streams. Origin of
name: from Latin spinella meaning little thorn, after crystal shape. Spinels
next to ruby and the rare red diamond, is the most expensive of all red gems.
With a hardness of 8 and no cleavage planes, natural spinel is a tough and
durable gemstone suitable for any kind of jewellery. Unfortunately most
Spinel that is sold commercially is synthetic.
Colour: cobalt blue, red to blue to mauve. Dark green, brown, blackgreen, pink, deep pink with an orange tinge. Hardness:8 |
TANZANITE
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Tanzanite is
part of the zoisite mineral species and is only found in
Colour:Tanzanite is noted for its remarkably strong trichroism, appearing alternately sapphire blue, violet, and sage-green depending on crystal orientation. (Trichroism is the property possessed by certain minerals of exhibiting three different colours when viewed from three different directions under white lights. However, most tanzanite is subjected to artificial heat treatment to improve its colour and this significantly subdues its trichroism. Hardness: 6.5 N.B: Tanzanite is a brittle stone and although it can be worn daily, care should be taken to protect it from knocks, pressure and extreme temperature changes. Do not use a home ultrasonic to clean jewellery with tanzanite |
TOPAZ
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Topaz is a
fluorosilicate and can contain trace elements that cause different colours
within the Topaz. Origin of name: from Greek Topazion, a
Colour: Varies in a broad range of: yellow, blue, pink, peach, gold, green, red, and brown. Hardness: 8 N.B. Topaz is often heated to change or enhance it's colour. |
TOURMALINE
|
Tourmaline
is one on the most complex gemstones of the silicate group and there are 10
different varieties created by the dozen or more elements they contain.
Origin of name: from Sinhalese turamali = stone of mixed colours. There are
Tourmalines, which change the colour from daylight to artificial light and
others display chattoyance(a mobile, wavering striped reflection).Tourmaline
is found in Africa,
Colour: depending on the variety green, red to pink, light to dark blue, colourless, purple , neon blue, brown, black, red to green and green to red. Hardness:7-7.5 N.B. Tourmaline may be heated to enhance it's colour. |
TIGERS EYE
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Tigers Eye
is mainly composed of silicon dioxide, it is a form of quartz that acquires
fine golden lustre when polished. Origin of name: the stone resembles the eye
of a tiger. Tiger's eye is a semi precious stone with a rich yellow and
golden brown stripes that display chattoyance(a mobile, wavering striped
reflection). Tigers eye is found in regions of
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TURQUIOSE
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Turquoise is
composed of aluminium phosphate and copper. Origin of name: from French for
Turkish stone as in ancient days it was transported through
Colour: Blue, blue-green, green Hardness: 5-6 |
NATURAL ZIRCON
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Zircon is
zirconium silicate, belonging
to the group of nesosilicates. Origin of name: from Arabic zarqun and Persian
zar = gold, gun = colour. Zircon is a natural forming mineral and it is not
related to the synthetic diamond substitute Cubic Zirconium which is created
in a laboratory. Zircon has a high refractive index and can be used to
imitate diamonds. It is found in
Colour: Zircon can come in red, brown, yellow, green, black or colourless. The colour of zircons below gem quality can be changed by heat treatment. Depending on the amount of heat applied, colourless, blue and golden-yellow zircons can be made. Hardness: 7.5 |
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