Cordierite (iolite)

Conch Pearl

The blue gemstone with pleochroism

overview

Naming : Originally (at the beginning of the 19th century), iolite was called diochrite because of its two colors (dichroism). However, as it was later recognized that iolite is not only two-colored, but a pleochroistic gemstone, it was later renamed cordierite - after the French mineralogist Louis Cordier. The third name, which is the most common today, especially in the English-speaking world, is iolite. The name iolite also refers to the color of the gemstone: in Greek, the word ion means "violet" and lithos is "stone".
Mineral group: Cordierite (iolite) forms its own mineral group.
Color: Iolite (also cordierite) is a mostly blue to blue-violet gemstone. Sometimes there are also colorless or pale blue iolite gemstones, but they are extremely rare.
Cut : Cordierites are usually faceted because the faceted cut particularly highlights the transparency of the gemstone.
Special feature: Iolite has the extraordinary property of pleochroism, which means that the gemstone has a different color depending on the light. Colors range from yellow to violet to light blue.

Color

The most sought-after colors of cordierite are violet-blue to a fine blue.

purity

Correctly oriented inclusions can produce a cat's eye effect in cordierite.

carat

High-quality cordierites weighing over 5 carats (ct) are extremely rare. The carat number indicates the weight of a gemstone. One carat weighs 0.2 grams. The carat number is very important for the value of a gemstone. However, the color, cut and clarity also play an important role.

cut

Cordierite is usually processed into a facet cut, as this particularly highlights the transparency of the gemstone.

The impressive play of colors of iolite – pleochroism

Iolite is usually dark blue or blue-violet. The inclusion of hematite or goethite can give the iolite a reddish to brown color. Very rarely there are also gray or colorless variations. The true color of iolite only appears in neutral light. Under the light of neon light, for example, the gemstone can appear in a completely different color. Iolite is a gemstone with a very pronounced pleochroism. Depending on the light, iolite therefore appears in different colors. The color play of iolite includes the three colors yellow, violet and blue.

Special Cordierite

The Most Desired

Faceted cordierites of high quality weighing over 5 carats are extremely rare.

The Greatest

The largest iolite ever found weighs more than 24,000 ct. The gemstone was found in Wyoming in the United States.

Special occasions

wedding anniversary

Iolite is the gemstone for the 21st wedding anniversary.

occurrence of cordierite

The most important locations where iolite has been found are in Brazil, India, Madagascar, Myanmar, Norway, Sri Lanka, the USA and Canada. Iolite has also been found in Bodenmais, Germany.

Jewelry with Cordierite

Are you interested in a loose iolite gemstone or iolite jewelry? You can customize RENÉSIM's exclusive jewelry yourself and create, for example, a breathtaking iolite ring. We would be happy to help you with your selection. Please contact us using the form below or by phone.