SAPPHIRE IN JEWELRY

SAPPHIRE CHARACTERISTICS

The sapphire is a gemstone, just like the emerald, diamond, and ruby. It belongs to the corundum family. Corundum is a mineral species defined by three key characteristics:
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1. Exceptional durability
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Ranking 9 out of 10 on the Mohs scale, the sapphire is the second hardest natural mineral on the planet, surpassed only by the famous diamond! In practical terms, this means that no natural stone can scratch it, with the exception of another sapphire or a diamond.

Note: Moissanite is a lab-grown stone with a hardness level falling between that of diamond and sapphire.
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2. Iconic colors
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One of the defining features of corundum is its wide range of colors. The most famous, of course, are red (for rubies) and blue.
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Ranging from light to dark blue, the sapphire offers a vast spectrum of shades.
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3. Corundum is extremely heat-resistant
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Sapphires are highly resistant to thermal shock and high temperatures. Their melting point is around 2,000°C—a temperature you are unlikely to encounter in everyday life :)
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SAPPHIRE QUALITY
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The highest grade for a colored gemstone is AAA quality.
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Unlike diamonds, colored gemstones lack standardized, internationally recognized grading systems for comparison.
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That said, the certification process for a colored gemstone—such as a sapphire—is just as rigorous as that for a diamond and corresponds to three quality levels:

• A denotes average, common quality.

• ​AA denotes a rarer quality, typically found with small local lapidaries rather than major retailers. It represents superior quality, with few flaws and rich, intense colors.

• AAA is the highest possible quality for colored gemstones. It signifies a complete lack of flaws, superior brilliance, and rich, uniform color.

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How is this quality assessed for a sapphire?
 

It is based directly on the universal "4Cs" used for diamond certification!
Namely:

• Color: whether it is natural or enhanced by treatment,

• Uniformity: whether the color is even or shows "zoning."

• Weight: the stone's carat weight.

• Cut (or faceting): an evaluation of the stone's faceting quality and shape.

• Clarity: the presence or absence of inclusions visible to the naked eye or under 10x magnification.

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FREQUENTLY ASKED QUESTIONS
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Are sapphires treated?
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The vast majority of natural colored gemstones worldwide undergo heat treatment.
 

What does this mean?
 

Heating a gemstone is a process that has been used since ancient times to enhance, stabilize, or simply strengthen the stone's color and durability. It is a process that does not harm the stone, so there is no need to worry about it.
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Contrary to popular belief, unheated stones are quite rare; unless explicitly stated or backed by a specific certificate, it is unlikely that a stone is unheated. Be wary if you are told a sapphire is unheated but lack a certificate from an independent laboratory. An unheated stone with intense color is so rare that it commands a very high price. Although this process does not correspond to a specific type of treatment, it must obviously not be confused with chemical treatments—such as irradiation, fracture filling, impregnation, and dyeing—which are regulated by the State because they alter the stone's natural state.