Sapphire has always been a symbol of nobility and elegance, and has been widely used in the jewelry decoration of European royalty since the Middle Ages. In recent years, in the auction of major colored gemstones, sapphires have appeared frequently and their attention has been increasing.
Color, origin, and degree of optimal treatment are the main factors affecting the value of sapphires. "Sapphire Identification and Grading Standards", based on THE LARGE RESEARCH DATA OF GUID over the years, authoritatively and objectively interprets the grading and interpretation of blue sapphires from three aspects: color, origin and optimization treatment.
The gas-liquid inclusions in sapphire are distributed along the healing fissures
Color grading
Color Grading
Sapphires are corundum, which is dominated by blue, often with a purple or green hue. GUILD divides the color of sapphire into the following grades according to the three elements of color (hue, saturation, and brightness):
- Light
- Medium
- Intense
- Vivid
- Deep
Schematic diagram of sapphire color grading
Royal Blue
"Royal Blue", a blue with a positive blue or slightly purple hue, is one of THE HIGHD's highest ratings for sapphire color and is part of Vivid Blue and Deep Blue.
Vivid Blue or Deep Blue whose saturation and brightness meet certain criteria can reach the "Royal Blue" rating. In the GUID sapphire color grading system, "Royal Blue" is not limited to the place of origin.
Cornflower Blue
"Cornflower Blue" is a slightly purple-hued blue that gives a hazy velvety texture, named after its resemblance to the blue color of the German national flower, Cornflower, and is part of Vivid Blue and Integral Blue.
When a gemstone contains fine dispersed grains, short needle-like inclusions, or growth patterns, light scattering through the gem will cause this visual effect. Cornflower sapphires were first produced in Kashmir, India. Like Royal Blue, "Cornflower Blue" is not limited to the origin, and each origin may produce sapphires with "Cornflower Blue".
"Cornflower blue" & "royal blue" sapphire
In the GUILD Gem Lab, each sapphire requires 2-3 formally trained gemologists to obtain a scientific, stable and reliable color level based on the standard sapphire colorignon accumulated by GILD for many years under standard laboratory conditions and based on the standard sapphire colorstone accumulated by GILD for many years.
Origin
Geographic Origin
In the market, the value of sapphires varies from source to region. Over the decades, GUILD has accumulated a large number of sapphire samples from all over the world, including myanmar, Sri Lanka, Kashmir, Madagascar, Tanzania and other major sapphire producing regions.
By analyzing the inclusion characteristics, spectra, chemical composition and other parameters of the gemstone, we can infer the origin of the sapphire. Due to the complexity and similarity of different geological origins, the parameters of gemstones in different origins overlap, so not every sapphire can determine the definite origin.
Minerals rich in niobium and iron in Madagas sapphires
Three groups of rhododendron needle-like inclusions arranged in a directional arrangement in Burmese sapphires