The Complete Sapphire Guide

Sapphire Consumer Information

As provided and validated by various gemmological organizations, laboratories and the "World Jewelry Confederation CIBJO"

Care

Sapphires are extremely durable due to their hardness and exceptional toughness
As with most gemstones, a soft moistened cloth, or a soft bristle toothbrush may be used to clean the gem

Treatment

Color: Consider all sapphires heat treated unless specifically guaranteed otherwise.
Color: Irradiation can create orange or yellow sapphires out of colorless stones. Color does not stay.
Color: Additional chemical elements can be “diffused” in the stone to enhance/change colors
Clarity: fissures can be filled with glass. This occurs more frequently in rubies than sapphires

Color

A corundum mineral is called ruby or sapphire, depending on the metallic oxides present which determine the colour. Sapphires come in every colour except red. The red corundum is a ruby.

The most prized blue colour is also known by a flower and is called “cornflower”
The rarest sapphires, “padparadschas” (named after the lotus flower), are orange-pink or pinkish-orange in colour
“Fancy” sapphires” are any “not blue” sapphires

Clarity

Inclusions in sapphire may be composed of fine rutile needles (called silk), which may intersect at 60-degree angles. In such cases, when the gem is cut as a cabochon, a star effect may occur
Inclusions can cause some gems to have milky colouration, this becomes a detriment if it also causes a perceived loss of blue
In top Kashmir sapphires the haziness from inclusions (called sleepiness) acts to diffuse light and colour resulting in even blue coloration

Cut

Sapphires are mostly cut in traditional pear, round, oval, cushion and emerald cut outlines.
They are sometimes engraved or carved today, though sapphires were sometimes engraved during India’s Mughal Era

Sapphire References in Antique Gemological Books

Edwin Streeter: Precious Stones

Famous and Influential English Jeweler Edwin Streeter on Sapphires. He led a consortium against Baron Rodthschild for the rights of the Burma Ruby mines.

Oriental Amethyst = Pink Sapphire

What is Oriental Amethyst (Tavernier in 17th century) .
Famous Italian Jeweler Castellani’s comments
Treatments, Quality of Oriental Amethyst
Engraved Oriental Amethyst (Greeks to French Crown Jewels)
Corundum and Sapphire Mining Localities Mines
Mason County | Jencks Mine | North Carolina Corundum
George F. Kunz | Sapphires and Corundum | North America
Montana Sapphires and 312 pound Sapphire of Jencks Mine Franklin N.C.
Anakie Sapphire Mines | Queensland | Australia
17th century Tavernier brought back the Hope Diamond from India. His take on Sapphire washings in Ceylon (Sri Lanka)
A list of more recent Corundum and Sapphire localities (Afghanistan | Burma | Ceylon)

Sapphire References before 1600

Father of Mineralogy Georg Agricola on Blue Gemstones such as Sapphires
Theophrastus on Sappheiros: Sapphire
Saint Albertus Magnus on Sapphires

Important Sapphire References

Oliver Farrington (curator Chicago’s Field Museum of Nat. Hist. 1894-1904). His Sapphires and Corundum chapter.
Famous Italian Jewelry Designer Castellani: Chapter on Sapphires

Other gemstone guides:

As provided and validated by various gemmological organizations, laboratories and the World Jewelry Confederation CIBJO