Sapphires come from the mineral corundum which comes in all shades of the rainbow. The color red is called a ruby.
Sapphires are the most popular colored stone and are a wonderful change from a diamond for a
beautiful engagement ring. More customers buy sapphires than any other colored stone. Among the colored stones, sapphire, emerald and ruby, sapphires and emeralds are the most affordable.
Color Quality
The fact that determines value in a sapphire is color, color, color. It comes in all “hues, tones and degrees of saturation” according to the Gemological Institute of America and “blue sapphires range from very light to very dark to very dark violetish blue to greenish blue”.
Velvety blue to violetish blue with strong to vivid saturation describes the
highest priced sapphire. In commercial jewelry stores, most sapphires are either very light or dark inky blue and are not considered the highest quality. Inky blue sapphires have a serious decrease in brilliance.
The finest quality of sapphire is the Kashmir sapphire. It has a violetish blue to pure blue hue. Cornflower blue is often the color description given to Kashmir sapphires.
Sapphire Size
Blue sapphires can range in size from a few points, (one hundred points equal a carat), to very large, being hundreds of carats. Sapphires under five carats will sell for only twice as much as a high quality one carat sapphire of the same quality. Commercial quality sapphires are more common than high quality sapphires.
Although sapphires have some inclusions, their clarity is still better clarity than rubies.
Inclusions
If there are many inclusions, it will affect the durability of the sapphire and makes it less valuable. Some inclusions do increase the value of the sapphire, such as in the Kasmir sapphire. Those tiny inclusions give the Kashmir sapphire their velvety appearance.
Heat Treatment
Heating increases the color and clarity of sapphires and it will retain their enhanced effects. Consider a stone to be treated unless otherwise disclosed.
