Crushed Indigo Iolite (Cordierite) from India, Coarse Crush, Gravel Size, 4mm - 2mm

Iolite, also known as cordierite, is a pleochroic mineral that changes from blue to violet-blue depending on the angle of light. It is believed that ancient Viking navigators used thin slices of iolite as filters to help determine the direction of the sun on overcast days (similar to polarized lenses). This particular crushed iolite is from India and has a semi-translucent indigo to violet color. 

Our coarse material is considered to be pea-sized gravel, ranging between 4 millimeters to 2 millimeters. Please see the corresponding sediment size chart.

Mineral Properties

• Mohs’s Hardness: 7 - 7.5
• Specific Gravity (g/cm3): 2.54-2.66
• Luster: Vitreous
• Color: Indio, Violet-Blue
• Origin: India

This product is not man-made, mixed with resin, dyed, or stabilized. Pictures are taken in full sun and material is dry. Size measurements are using the metric system (millimeters), including the metric ruler (cm/mm) as shown in the product photos.