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The name “sapphire” can also apply to any corundum that’s not ruby red, another corundum variety.

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Madagascar Beauty

This 7.04-ct. oval sapphire is from a new source, the island Madagascar.

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Blue Velvet

Deep, intense, velvety blue describes this sapphire’s color.

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Best in Daylight

Blue sapphire looks best in daylight and fluorescent light.

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Spindle Shape

This spindle-shaped crystal from Sri Lanka weighs 70.10-cts.

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Color Zoning

Blue color distribution in sapphire crystals is often uneven.

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There is a second sapphire crystal growing into the larger one.

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Buyer's Guide

Sapphire is one of the Big 3 of jewelry gemstones—the other two are ruby and emerald. Sapphire is a durable stone that’s the best known blue gem, as well as being available in most colors.


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What To Look For

Intense Blue Sapphire
Color Is The Most Important Quality Factor For Sapphire

The most highly valued blue sapphires are velvety blue to violetish blue, in medium to medium dark tones. Preferred sapphires also have strong to vivid color saturation. The saturation should be as strong as possible without darkening the color and compromising brightness.

Star Sapphire
Clarity Refers To The Inclusions

Blue sapphires often have some inclusions. Blue sapphires with extremely high clarity are rare, and very valuable. Price can drop if the inclusions threaten the stone’s durability. Kashmir sapphires contain tiny inclusions that impart a desirable velvety appearance.

3.03-carat Radiant-cut Sapphire
Cut Is One Of The Most Important Factors In Appearance

To achieve the best overall color, maintain the best proportions, and retain the most weight possible, cutters focus on factors like color zoning, pleochroism, and the lightness or darkness of a stone.

Vagabonde Bleue Ring
Carat Weight Allows For Precise Measurements

Blue sapphires can range in size anywhere from a few points to hundreds of carats, and large blue sapphires are more readily available than large rubies. However, most commercial-quality blue sapphires weigh less than 5.00 carats.

Sapphire Quality Factors: The Comprehensive Guide

Tips & Advice

1. Work with a jeweler to understand the difference that color makes.

Look at different colors of sapphire side by side to understand the range of qualities available. Dark colors like navy or midnight blue, and less saturated colors like grayish blue or straw yellow are more affordable than vivid colors.

2. Don’t compromise on cut.

The quality of the cut can make a big difference in beauty and brilliance. Your sapphire should sparkle in a lively way, reflecting light back evenly across the entire gem. Poorly cut gems are much less marketable and sell at a discount.

3. Ask about the type of treatment a sapphire has undergone.

A large amount of the sapphire on the market, both blue and fancy colors, has been treated to alter its color by heat or by lattice diffusion. Sapphire treated by lattice diffusion often has vivid color but is less valuable than heated sapphire. When in doubt, get a lab report.