Cordierite is not a well known or popular mineral for mineral collectors. However, its gemstone variety is well known and is rather popular among gemstone collectors and fanciers. The gemstone variety of cordierite is called iolite.

Its unusual blue-violet color is attractive and is compared to a light blue sapphire with a purplish tint. It is the reason that cordeirite is sometimes called "water sapphire". One of the most notable characteristics of cordierite is its strong pleochroism, or color changing ability. When viewed from one direction, the crystal or gemstone may appear blue or blue-violet. But as the crystal or gemstone is rotated to another viewing direction, the color will appear yellowish gray to light blue.

Color	Deep blue to violet blue,light blue, or greyish blue
Refractive Index	1.542-1.578
Pleochroism	Very strong
Chemistry	magnesium aluminum silicate
Hardness	7-7.5
Density	2.58-2.66
Crystal Group	Orthorhombic
Ocurrence	Germany(Bavaria), Norway, Finland, Brazil, Burma (Myanmar), India, Sri Lanka, United States, Madagascar

The pictures above only represents the general appearance of the Cordierite. Please note that the real Cordierites in our stock will be of varied shapes, color and sizes.