Iolite Facts

Iolite Facts

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Iolite Properties

Chemical Composition It is Magnesium Aluminum Silicate and the chemical formula is Mg2Al4Si5O18.
Colours Violet blue, violet, yellowish gray, blue and bluish violet
Specific Gravity 2.53 – 2.78
Refractive Index 1.52 – 1.57
Luster Viterous.
Hardness 7 – 7.5 Mohs
Solid State Transparent.
Pleochroism Very high.
Fractures Uneven / conchoidal / brittle
Bi-refringence 0.001
Crystal System Orthorhombic crystal system.
Cleavage Distinct in 3 directions.
Heat Sensitive No
Dispersion Medium 0.017
Precautions Protect from sharp blows, direct sunlight, excessive heat, large temperature change. Avoid home ultrasonic cleaner.
Enhancement None
Source Sri Lanka, India, Madagascar, Burma, Zaire, Mozambique, Zimbabwe, Germany, Finland, Brazil, Canada, USA and Tanzania
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