Also called cordierite, after its discoverer, iolite derives its name from the Greek word for “violet.” Iolite is a lovely transparent gemstone that ranges in color from blue to deep violet-blue.
Iolite is strongly pleochroic, which means that its color changes dramatically when viewed from different angles. When viewed from one angle iolite may appear grey, from another angle deep blue, and from a third angle iolite appears almost colorless.
Legendary Norse Sunstone
The curious pleochroic property of this gemstone likely makes iolite the “sunstone” written of in ancient Norse sagas. The Vikings used the sun to help them navigate, but if the sun was low in the sky or if the sky was overcast, then Vikings used iolite to help them find the direction of the sun. When held up to the sky, sunlight would pass through the stone, making the stone appear colorless at a certain angle, from which the Vikings could calculate the direction of the sun and find their way.
A Difficult Stone to Cut
Iolite’s pleochroism may have been helpful in navigation but it certainly makes life difficult for the cutter. If iolite is not cut from exactly the right direction, no matter what the shape of the raw crystal, its color will not be shown to its best advantage.
No Longer a Collector’s Stone
Due to its scarcity before 1980, iolite was known only as a collector’s stone. Today iolite is relatively available and makes an affordable alternative to sapphire.
Due to its similarity to sapphire, faceted iolite is sometimes misleadingly referred to as water sapphire.
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