Sapphire selection differs from one person to another. However, the generally accepted method of selecting the â€œrightâ€?sapphire is based on the 4 Cs â€?colour, clarity, cut and carat.
The colour of a sapphire is determined by its hue, saturation and tone. Hue is the basic colour of a gemstone. Generally, gemstones with purer hues (for sapphires, blue) are more valuable. Often, other colours are also detected. Mushan provides sapphires of all colours: blue, pink, yellow, violet, white, green, orange, and pink-orange (padparadscha). Amongst blue sapphires, we specialise in a range of hues, including vivid blue, cornflower blue and royal blue.
Saturation is a measure of the intensity and purity of a gemstoneâ€™s hue. Usually, value increases with saturation. The tone of a gemstone is a measurement of its lightness or darkness.
A flawless sapphire is rare and usually extravagantly priced. Like most gemstones, sapphires have inclusions (tiny mineral flaws) that can be seen under magnification or by the careful eye.
Sapphires tend to be moderately included, while emeralds and rubies are usually heavily to moderately included. Clarity grades range from VVS (very, very slightly included) to I3, in which inclusions are prominent and severely affect the gemstoneâ€™s beauty.
A sapphireâ€™s cut refers to its proportions and symmetry. A sapphire should be symmetrical in all dimensions to appear balanced and so that its facets reflect light evenly, providing brilliance. Colour should also be taken into account â€?if a stoneâ€™s colour is highly saturated, a shallow cut will allow it to pass more light, while a deeper cut may increase the vividness of a less saturated gem.
Although a gemstoneâ€™s weight is usually given in carats, this may not give an accurate idea of its size because different types of stones have different densities. Therefore, a 1-carat sapphire or ruby will be smaller than a 1-carat emerald, even though they have the same weight, because sapphires and rubies (both a form of the mineral corundum) are denser than emeralds.