How to determine the price of a star sapphire?
The value of star sapphires is basically influenced by two things: (a) The strength and sharpness of the star, (b) Intensity and attractiveness of body colour Cutting: All star sapphires are cut as medium to high domed-cabochons. This is necessary to display the star effect. Most star sapphire cabochons are round or oval shaped. Usually the bottoms of the cabochons are left unpolished to prevent light from escaping from the gemstone. The star should be properly centered when the gem rests on its base. Colour: Although star sapphires occur in a variety of colors, the supply of fine stones is always limited. Black star sapphires which range from translucent to opaque are often very dark brown, green, or blue, rather than true black. Black stars are the most readily available and least expensive natural star stones. Green star sapphires are rare and yellow or orange ones are very rare. It is extremely rare to find a star-sapphire with a sharp star and a bright blue body color. Also it mus