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Sapphire
Mohs hardness 9, Specific gravity 4, Refractive index
1.760–1.770. Sapphire name comes from Greek sappheiros "blue stone" is a
gemstone variety of the mineral corundum, an aluminium oxide. Colour
other than red or dark pink, in which case the gem would instead be
called a ruby, considered to be a different gemstone. Trace amounts of
other elements such as iron, titanium, or chromium can give corundum
blue, yellow, pink, purple, orange, or greenish colour. Pink-orange
sapphires are also called padparadscha. A combination of chromium and
titanium can give a sapphire of a colour distinct from red. The cost of
natural sapphires varies depending on their colour, clarity, size, cut,
and overall quality - as well as their geographic origin. Significant
sapphire deposits are found in Eastern Australia, Thailand, Sri Lanka,
Madagascar, East Africa, and in North American at a few locations, such
as at "Gem Mountain", and in or near the Missouri River in the region
around Helena, Montana. Blue sapphires are evaluated based upon the
purity of their primary hue. Purple, violet, and green are the most
common secondary hues found in blue sapphires. Violet and purple can
contribute to the overall beauty of the colour, while green is considered
to be distinctly negative. Yellow and green sapphires are also commonly
found. Pink sapphires deepen in colour as the quantity of chromium
increases. The deeper the pink colour the higher their monetary value as
long as the colour is trending towards the red of rubies.
Sapphires also occur in shades of orange and brown, and colourless sapphires are sometimes used as diamond substitutes in jewellery. Padparadscha sapphires often draw higher prices than many of
even the finest blue sapphires. A star sapphire is a type of sapphire
that exhibits a star-like phenomenon known as asterism. Star sapphires
contain intersecting needle-like inclusions of the mineral rutile, a
mineral composed primarily of titanium dioxide, that cause the
appearance of a six-rayed "star"-shaped pattern when viewed with a
single overhead light source. A rare variety of sapphire, known as colour
change sapphire, exhibits different colours in different light. Colour
change sapphires are blue in outdoor light and purple under incandescent
indoor light; they may also be pink in daylight to greenish under
fluorescent light. Some stones shift colour well and others only
partially, in that some stones go from blue to bluish purple.
In 1902, the French chemist Auguste Verneuil developed a
process for producing synthetic sapphire crystals. In the Verneuil
process, named for him, fine alumina powder is added to an oxyhydrogen
flame, and this is directed downward against a mantle. The alumina in
the flame is slowly deposited, creating a teardrop shaped of sapphire
material. Chemical dopants can be added to create artificial versions of
the ruby, and all the other natural colours of sapphire, and in
addition, other colours never seen in geology. Artificial sapphire
material is identical to natural sapphire, except it can be made without
the flaws that are found in natural stones.
DARK BLUE SAPPHIRE - inspires
creative expression, intuition and meditation. GREEN SAPPHIRE brings
luck.
ORANGE SAPPHIRE - also known as
Padparadschah, augments wisdom, optimism and friendliness.
PINK SAPPHIRE - encourages generosity, love
and loyalty.
STAR SAPPHIRE - develops independence,
centering, balance and psychic.
WHITE SAPPHIRE - associated with
self-appreciation and spiritual development.
YELLOW SAPPHIRE - enhances intellect,
study, knowledge and memory.
April Ancient traditional birthstones: Hebrew - sapphire,
Roman - sapphire, Arabic- sapphire
July Ancient traditional birthstones: Hindu - sapphire
September Modern birthstone: sapphire
Zodiac gemstone for Taurus: sapphire
Guardian angel Verchiel his talisman stone - sapphire
Sapphire care: Wash with warm soapy water, Avoid harsh
detergents, Ultrasonic and steam cleaning are usually safe.
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