Iolite stone

By Yves Lemay Jun 17, 20

Iolite stone

Chemistry: (Mg, Fe2) Al4Si5O18

Crystallography: Orthorhombic

Refractive index: 1.522 - 1.578

Hardness: 7 - 7.5

Specific gravity: 2.53 - 2.78

Cleavage: Distinct 1 direction

Heat sensitive: No

Wearability: Very Good

Special care instructions: None

Enhancements: None

iolite stone yves lemay jewelry

The name iolite comes from ios, the Greek word for violet. 

Like sapphire and tanzanite, its fellow blue gemstones, iolite is pleochroic- meaning it transmits light differently when viewed from different directions. 

The Vikings made iolite's pleochroism a virtue by using thin slices of the stone as a light polarizer to navigate their trips. 

By observing the sky through iolites, the Viking navigators were able to locate the exact position of the sun on overcast days. 

Iolite does what a Polaroid does- it cancels out haze, mist, and clouds to make things appear clearer. 

In fact, the stone has been called the "Viking's Compass." 

iolite stone yves lemay jewelry

Only officially named in 1912, iolite has been used and admired for centuries. 

It was prevalent in jewelry in the 18th Century in Europe but today it is used somewhat infrequently.It is one of the few relatively available and affordable blue stone options, is rapidly gaining in popularity. 

Arguably the gain is due more to exposure in mail-order catalogs and on cable shopping channels than to promotion by traditional jewelry stores. 

It often has a steely, inky, or washed out blue color, but the best specimens can rival AAA tanzanite in the saturation of their blue-violet hue.

iolite stone yves lemay jewelry

Iolite is frequently step cut to enhance color and often windowed and/or shallow cut to lighten the tone. 

The cutter must orient the rough carefully, taking iolite's trichroism of blue, gray, and near colorless into account. 

So far, no treatments have been successfully used to lighten the color or to remove inclusions, so one can assume that these gems are untreated.

iolite stone yves lemay jewelry

Its hardness of 7-7.5 makes it a suitable jewelry use, though the cleavage must be taken into account. 

Most of the iolite in world commerce comes from India, but substantial amounts are also mined in Tanzania, Brazil, and Sri Lanka.

iolite stone yves lemay jewelry

Thanks for reading, and please feel free to share this article with your contacts!

The GIA colored stone grading system
The beautiful color of a gemstone is its most defining characteristic, and many jewelers consider it to be the most...
How to appreciate the quality of jewelry (before you buy)
When it comes to appreciating the quality of a piece of jewelry, there are three major things you must look for: -Base...
Everything that you need to know about jewelry metals
If I say the word "ring," the first image that will come to mind for most people will be yellow-colored....
The 4 types of pearls that you need to know before purchase
There are two major types of cultured pearls; freshwater and saltwater pearls. Freshwater pearls primarily come from China.Saltwater pearls, which include...
The 6 cultured pearls quality factors
There are 6 main factors to keep in mind when determining a pearl's quality and worth: Nacre, Luster, Surface, Shape,...
How pearls are made
Pearls are unique among gemstones, being the only ones found within a living creature and the only ones that require...

Leave a Comment