of these articles is occupied with the mineral sapphire. For the French rocket of the same name see sapphire (rocket).
raw sapphire
Chemismus aluminium 2 O 3
crystal system trigonal
Kristallklasse < math> \ overline {3}< /math> m
color blue; in the broadest sense hardness 9 relative density
3,95 knows
all colors
except red line color- 4.03
gloss Glasglanz
opacity transparent to obscurely
break muschelig, splitterig, spröd
fissileness no
Habitus on both sides intensified, tonnenförmig, hexagonal pyramids, taflig
frequent crystal faces ___
twin accomodation ___
crystal optics
refractive index 1.76 - 1.77
birefringence -0.008
Pleochroismus ___
optical orientation ___
of the Zes-axis
2v z ~ ___
further characteristics
chemical behavior ___
similar minerals corundum, ruby
radioactivity not radioactively
magnetism not magnetically
special characteristics ___

than sapphire one designates each gem stone from corundum with exception of the ruby-red Varietäten (rubies) in the broader sense. Strictly speaking refersthe term today however only on the blue variants, which however still from sky blue to a going darkblue to reach and depending upon beam of light also in the colour to vary be able.

Sapphire consists 2 O 3 of monocrystalline aluminium as well as depending upon colorImpurities with Fe 2+ -, Fe 3+ -, CR 3+ -, Ti 4+ - and/or V 4+ - ions. The hardness amounts to 9 on the Mohs scale.

Table of contents

occurrences andartificial production

of sapphires arise in Pegmatiten or by decomposition spent in river sediments.

The most important producers of sapphires were until recently Sri Lanka and India, today come the gem stones also from the USA or Nigeria.

Artificial sapphires can in perfect quality inalmost unlimited size to be manufactured.


apart from its use as gem stone was used the sapphire in Schallplattenspielern of the 1950er and 1960er years as point of the Tonabnehmernadel.

Synthetic single-crystal sapphire of substrates is the most important raw material for the artificial crystal growth (epitaxy) of Gallium nitride, a substance, which is used in blue, white and green LEDs as well as blue diode lasers.

Under admixture of titanium as Laserion synthetic sapphires also are an important component for lasers - applications, in particular for tunable lasers in the wavelength coverage of 750 to approximately 1000 nanometers; these become short as titanium sapphire lasers, Ti: SA laser marks.

For the extreme loads suspended windows of reconnaissance planes or space missiles synthetic sapphires are used of up to 75 centimeters diameters.

In special cases sapphire finds also in scientific instruments with space travel use, for examplethe genesis mission.

individual sapphires

the largest ever polished sapphire is the “star of India” with a weight of 563.35 carat. The stone found in Sri Lanka was conveyed to 1901 by John Pierpont Morgan to the American museum OF Natural Historyand can be visited there.


the sky-blue variant is usually brought with characteristics such as peace, purity and peace in connection.

See also: List of minerals

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