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Iolite

According to legend, Vikings used iolite slices to reduce glare when checking the sun’s position.

Iolite
See Gem As

BUYER'S GUIDE

Iolite’s most valuable color is a beautiful, saturated violet to blue. Unless inclusions cause phenomena such as aventurescence or chatoyancy, their presence makes iolite less valuable.

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WHAT TO LOOK FOR

COLOR
Vivid violet to blue are iolite’s best and most valued colors. It is highly pleochroic, so a cutter must orient the cut of the stone carefully so the best color shows through the gem’s table. Commercial-quality iolite often has a grayish color component.

CLARITY
Generally, eye-clean iolite is most valuable, but the presence of certain types of inclusions in the proper orientation can result in cat’s-eye or aventurescent gems. Phenomenal iolite is rare and coveted by collectors

CUT
Iolite is strongly pleochroic and has one direction of perfect cleavage. These properties can pose challenges during the fashioning process. A skilled cutter can bring out all the beauty iolite has to offer.

CARAT WEIGHT
Fashioned iolites that weigh from 1 to 10 carats can be found on the market. However, fine faceted iolites over 5 carats are somewhat rare.

Iolite Quality Factors: The Comprehensive Guide

QUESTIONS & ANSWERS

  • Q

    WHY ISN’T IOLITE AS POPULAR AS TANZANITE?

    A

    Iolite is found all over the globe, but it’s not as widely recognized as tanzanite. Some experts believe that jewelry designers and retailers don’t see a consistent enough supply of fine-quality iolite to feel confident about ordering a large selection for use in jewelry lines.

  • Q

    I UNDERSTAND IOLITE CLEAVES. IS IT TOUGH ENOUGH FOR RINGS?

    A

    Iolite is less durable than gems like diamond or sapphire. Because it is vulnerable to sharp blows, wearing an iolite ring during sports or at the gym isn’t recommended. However, with proper care and attention, many people wear iolite rings for years without any issues.

  • Q

    Does GIA grade iolite?

    A

    GIA evaluates iolite but does not grade it. A GIA Colored Stone Identification Report assesses the characteristics of a mounted or loose colored stone (weight, measurements, shape, cutting style and color), indicates whether it is natural or laboratory-grown and names any detectable treatments.

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Questions & Answers

CARING FOR YOUR IOLITE

Keep your iolite jewelry beautiful by following simple care and cleaning guidelines.

DURABILITY

DURABILITY

Because of its cleavage, extreme pressure or sharp temperature changes might cause iolite to break.
CARE AND CLEANING

CARE AND CLEANING

Warm, soapy water is always safe for cleaning iolite.
TREATMENT

TREATMENT

Iolite is not typically treated, so coatings, dyes, and fillers are not a concern.

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The Complete Guide on Caring for your Iolite

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