|The name iolite comes from the Greek ios, which means violet. Iolite is sometimes known as “water sapphire” because of its light violet blue colour, but other iolite gemstones may range from clear to honey yellow.
The ability of iolite to exhibit different colours depending on how it is cut is what led Viking explorers to use it for navigation as a polarizing lens to look directly at the sun.
|Violet blue to honey yellow to clear
||Composed of hydrous magnesium and aluminium silicate with a hardness that resembles quartz. Mohs hardness rating of 7 – 7.5.