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Sapphire

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 colour.

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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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Colour Zoning

Blue colour distribution in sapphire crystals is often uneven.

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Twinned

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

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Tools

Buyer's Guide

Sapphire is one of the Big 3 of jewellery 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 colours.

FIND A JEWELLER

Use your postcode to find a jeweller near you with GIA reports and GIA-trained staff.

FIND A REPORT

Verify the information on your report matches what is archived in the GIA report database.

What to look for

Intense blue sapphire
Colour 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 colour saturation. The saturation should be as strong as possible without darkening the colour 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 colour, maintain the best proportions and retain the most weight possible, cutters focus on factors like colour 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 jeweller to understand the difference that colour makes.

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

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 colours, has been treated to alter its colour by heat or by lattice diffusion. Sapphire treated by lattice diffusion often has vivid colour but is less valuable than heated sapphire. When in doubt, get a lab report.