Blue Sapphire Key Concepts

What is the name of the type of sapphire that is considered the finest?

What is the typical tone of highly valued blue sapphires?

Where are most fine sapphires over 100 carats typically from?

What elements cause the blue color of sapphire?

What is a common characteristic of sapphires that cutters must consider?

What percentage of commercial-quality blue sapphires are heat-treated?

Which of the following is a major center of the corundum trade?

What is unique about Yogo Gulch sapphires?

Where is one of the world’s major sources of dark blue, commercial-quality sapphires?

Blue Sapphire Characteristics

Fine-quality, untreated sapphires make up a small but extremely valuable segment of the sapphire market.
The most highly valued blue sapphires are velvety blue to violetish blue, in medium to medium-dark tones, with strong to vivid saturation.

Origin of Blue Sapphires

Madagascar has become a significant source of good- to fine-quality blue sapphire.
Most fine sapphires over 100 carats are from Sri Lanka.
Australia is one of the world’s major sources of dark blue, commercial-quality sapphires.
Yogo Gulch sapphires are characterized by small size and saturated blue color, and do not require heat treatment.

Cause of Blue Color

The trace elements iron and titanium cause the blue of sapphire.
Higher levels of iron make basalt-related sapphires darker than non-basaltic sapphires.

Trade and Treatment

The trade term “Kashmir” refers to what many consider the finest blue sapphires.
Most blue sapphires are heat-treated to improve their appearance.
Heat-treated geuda and dhun make up a significant portion of the commercial-quality blue sapphire market.
Thailand is a major center of the corundum trade, funneling a steady flow of gems from worldwide sources into the consumer market.

Test your knowledge about blue sapphire, a highly valued and popular colored stone. Learn about its sources, quality, and characteristics. Discover the most prized tones and hues of blue sapphire.