about ioliteS

Iolite is the word we use in gemology, but you may also know it under the name cordierite, which is more commonly used in mineralogy.

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General Information
Iolite is the term used in gemology, although it is also known as cordierite, which is more widely used in mineralogy. Cordierite is a cyclosilicate of magnesium and iron. It was named after the French geologist Louis Cordier after being discovered in 1813 in extracts from Njar, Almera (Spain). Some geologists might refer to blue iolite as steinheilite, after Fabian Steinheil, the Russian military governor of Finland who discovered it was not quartz.

Iolite is relatively common in hornfels formed by pelitic contact metamorphism. Geologists previously used this term to describe clay-rich, fine-grained clastic sediment or sedimentary rock, such as mud or mudstone.
Blue iolites available in Bulk at GemMatrix. Please send us a short message via the "contact us" tab.
The Old Navigators And The Iolites.
The majority of the pleochroic colors of iolite are grey, violet, or even yellow. Back in the day, the Vikings made use of this feature. Legendary Viking explorers like Leif Eriksson is said to have carried a piece of iolite with them to help them navigate the open seas of the Atlantic Ocean and beyond. In overcast days, they used it to locate the sun and map their location. Iolite does, in fact, eliminate mist and haze. Historians believe the Vikings used it to determine the path of the sun on a cloudy day.

It functions by determining the direction of the sky's overhead polarization. Light sprinkled by air molecules is polarized in this manner, and the orientation of the polarization is at right angles to a line to the sun, except when the sun's disk is blurred by thick fog or lies just below the horizon. Mining would have most likely taken place in Norway and Greenland during Viking times.
Oval Iolite: 6x4mm - Round Iolite: 4mm
Iolite Properties
Iolites, which are one of the few comparatively available and inexpensive blue gemstone options, are rapidly gaining popularity. They get their name from the Greek word for violet, and the cool shades range from light to dark blue to violet, much like a flower. They are extremely pleochroic transparent to translucent gems.

Iolite is a rough stone that can withstand scratching, with a Mohs hardness of 7.0-7.5. It is, however, prone to fractures. As a result, iolite is an excellent choice for jewelry such as pendants, brooches, and earrings. Protective accessories arrangements can also aid in the prevention of fractures. They are a very durable gemstone when exposed to light, but they can be weakened when heated.

Chemicals (primarily acids) can also cause damage to the stone. Since ultrasonic and steam cleaning techniques are risky, we recommend that you clean your gemstone with soapy water instead.

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Benjamin Poudevigne
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With over ten years of marketing experience, I finally decided to settle down in Bangkok to work in an area that I have always been interested in: the gemstones industry. I'm still learning how the market works on a daily basis, and I enjoy sharing my experience with those who are interested in learning more about gems in general.