Sapphire

sapphire crystalstar sapphireBlue sapphiresapphiressynthetic sapphiresapphire glassstar sapphirespadparadschayellow sapphirePadmaraga
Sapphire is a precious gemstone, a variety of the mineral corundum, consisting of aluminum oxide with trace amounts of elements such as iron, titanium, chromium, vanadium, or magnesium.wikipedia
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Gemstone

gemgemsgemstones
Sapphire is a precious gemstone, a variety of the mineral corundum, consisting of aluminum oxide with trace amounts of elements such as iron, titanium, chromium, vanadium, or magnesium.
In modern use the precious stones are diamond, ruby, sapphire and emerald, with all other gemstones being semi-precious.

Corundum

Al 2 O 3 C'''orundumcorindon
Sapphire is a precious gemstone, a variety of the mineral corundum, consisting of aluminum oxide with trace amounts of elements such as iron, titanium, chromium, vanadium, or magnesium.
Corundum has two primary gem varieties: ruby and sapphire.

Sapphire jubilee

65th anniversary
A sapphire jubilee occurs after 65 years.
In 2017, the term sapphire jubilee or blue sapphire jubilee was coined for the celebrations to mark the 65th anniversary of the reign of Queen Elizabeth II (see Sapphire Jubilee of Queen Elizabeth II).

Jewellery

jewelryjewelledjeweler
Commonly, natural sapphires are cut and polished into gemstones and worn in jewelry.
As early as 2,000 years ago, they imported Sri Lankan sapphires and Indian diamonds and used emeralds and amber in their jewellery.

Titanium

Tititanium oretitanian
Sapphire is a precious gemstone, a variety of the mineral corundum, consisting of aluminum oxide with trace amounts of elements such as iron, titanium, chromium, vanadium, or magnesium.
Star sapphires and rubies get their asterism (star-forming shine) from the presence of titanium dioxide impurities.

Shandong

Shandong ProvinceShantungShantung Province
Significant sapphire deposits are found in Australia, Cambodia, Cameroon, China (Shandong), Colombia, Ethiopia, India (Kashmir), Kenya, Laos, Madagascar, Malawi, Mozambique, Myanmar (Burma), Nigeria, Rwanda, Sri Lanka, Tanzania, Thailand, United States (Montana) and Vietnam.
It also has one of the biggest sapphire deposits in the world.

Gemological Institute of America

GIAGIA (Gemological Institute Of America)Gemological Institute of America (GIA)
For most gems of one carat or more, an independent report from a respected laboratory such as American Gemological Laboratories (AGL), Gem Research Swisslab (GRS), GIA, Gübelin, Lotus Gemology, or SSEF, is often required by buyers before they will make a purchase.
Current research at gemological laboratories concerns the development of improved detection techniques for treated and synthetic diamonds, as well as for treated sapphires, rubies, and pearls.

Birthstone

Birthstonesbirthday stone
Sapphire is the birthstone for September and the gem of the 45th anniversary.

Light-emitting diode

LEDLEDslight emitting diodes
Because of the remarkable hardness of sapphires – 9 on the Mohs scale (the third hardest mineral, after diamond at 10 and moissanite at 9.5) – sapphires are also used in some non-ornamental applications, such as infrared optical components, high-durability windows, wristwatch crystals and movement bearings, and very thin electronic wafers, which are used as the insulating substrates of special-purpose solid-state electronics such as integrated circuits and GaN-based blue LEDs.
This avoids the typical costly sapphire substrate in relatively small 100- or 150-mm wafer sizes.

The Star of Adam

Star of Adam
At 1404.49 carats, The Star of Adam is claimed to be the largest blue star sapphire, but whenever such claims are made, one should be careful not to equate size with quality or value.
The Star of Adam is an oval-shaped blue star sapphire, currently the largest star sapphire in the world.

Black Star of Queensland

Black Star Sapphire of Queensland
The Black Star of Queensland, the second largest star sapphire in the world, weighs 733 carats.
The Black Star of Queensland, named after its nature and place of origin, is a 733-carat (146.6 g) black sapphire, and was the world's largest gem quality star sapphire until The Star of Adam was discovered.

Asterism (gemology)

asterismstar rubydiasterism
A star sapphire is a type of sapphire that exhibits a star-like phenomenon known as asterism; red stones are known as "star rubies".
The archetypal asteria is the star sapphire, generally corundum with near uniform impurities which is bluish-grey and milky or opalescent, which when lit has a star of six rays.

Chromium

Crchromechromium(III)
Sapphire is a precious gemstone, a variety of the mineral corundum, consisting of aluminum oxide with trace amounts of elements such as iron, titanium, chromium, vanadium, or magnesium.
If the corundum is lacking in chromium(III) ions, it is known as a sapphire.

Ruby

rubiessynthetic rubyR'''uby
The only color corundum stone that the term sapphire is not used for is red, which is called a ruby.
Other varieties of gem-quality corundum are called sapphires.

Titanium dioxide

TiO 2 titaniatitanium white
The inclusion is often the mineral rutile, a mineral composed primarily of titanium dioxide.
Star sapphires and rubies get their asterism from rutile impurities present.

Star of India (gem)

Star of India
The Star of India mined in Sri Lanka and weighing 563.4 carats is thought to be the third-largest star sapphire, and is currently on display at the American Museum of Natural History in New York City.
The Star of India is a 563.35-carat (112.67 g) star sapphire, one of the largest such gems in the world.

Star of Bombay

The 182-carat Star of Bombay, mined in Sri Lanka and located in the National Museum of Natural History in Washington, D.C., is another example of a large blue star sapphire.
The Star of Bombay is a 182-carat (36.4-g) cabochon-cut star sapphire originating from Sri Lanka.

Mohs scale of mineral hardness

Mohs hardnessMohs scalehardness
Because of the remarkable hardness of sapphires – 9 on the Mohs scale (the third hardest mineral, after diamond at 10 and moissanite at 9.5) – sapphires are also used in some non-ornamental applications, such as infrared optical components, high-durability windows, wristwatch crystals and movement bearings, and very thin electronic wafers, which are used as the insulating substrates of special-purpose solid-state electronics such as integrated circuits and GaN-based blue LEDs.

Watch

wristwatchwatcheswristwatches
Because of the remarkable hardness of sapphires – 9 on the Mohs scale (the third hardest mineral, after diamond at 10 and moissanite at 9.5) – sapphires are also used in some non-ornamental applications, such as infrared optical components, high-durability windows, wristwatch crystals and movement bearings, and very thin electronic wafers, which are used as the insulating substrates of special-purpose solid-state electronics such as integrated circuits and GaN-based blue LEDs.
Some are made entirely of faceted sapphire (corundum).

Boule (crystal)

boulesboulecrystal boules
They also may be created synthetically in laboratories for industrial or decorative purposes in large crystal boules.
The process is also used to create sapphires, which are used for substrates in the production of blue and white LEDs, optical windows in special applications and as the protective covers for watches.

National Museum of Natural History

USNMSmithsonian Museum of Natural HistorySmithsonian National Museum of Natural History
The 182-carat Star of Bombay, mined in Sri Lanka and located in the National Museum of Natural History in Washington, D.C., is another example of a large blue star sapphire. The 423 carat Logan sapphire in the National Museum of Natural History, in Washington, D.C., is one of the largest faceted gem-quality blue sapphires in existence.
The collection includes some of the most famous pieces of gems and minerals including the Hope Diamond and the Star of Asia Sapphire, one of the largest sapphires in the world.

Myanmar

BurmaBurmeseBurma (Myanmar)
Significant sapphire deposits are found in Australia, Cambodia, Cameroon, China (Shandong), Colombia, Ethiopia, India (Kashmir), Kenya, Laos, Madagascar, Malawi, Mozambique, Myanmar (Burma), Nigeria, Rwanda, Sri Lanka, Tanzania, Thailand, United States (Montana) and Vietnam.
Myanmar produces precious stones such as rubies, sapphires, pearls, and jade.

Verneuil process

flame fusionVerneuila process
In the flame-fusion (Verneuil process), fine alumina powder is added to an oxyhydrogen flame, and this is directed downward against a ceramic pedestal.
It is primarily used to produce the ruby and sapphire varieties of corundum, as well as the diamond simulants rutile and strontium titanate.

Ilakaka

Madagascar is the world leader in sapphire production (as of 2007) specifically its deposits in and around the town of Ilakaka.
After the discovery of one of Earth's largest known alluvial sapphire deposits in the valley in 1998, the population had boomed to nearly 60,000 in 2005.

Cabochon

en cabochoncabochonscabouchon
The stones are cut en cabochon, typically with the center of the star near the top of the dome.
In the case of asteriated stones such as star sapphires and chatoyant stones such as cat's eye chrysoberyl, a domed cabochon cut is used to show the star or eye, which would not be visible in a faceted cut.