Indicolite Tourmaline is the blue to blue-green variety of tourmaline, prized for its striking color and clarity. Here’s a detailed description:

Color

• Ranges from light sky blue to deep sapphire-like blue.

• Often has a teal or greenish undertone due to trace amounts of iron.

• The purest blues are rare and highly valued.

Chemical Composition

• Belongs to the tourmaline group, a complex borosilicate mineral.

• The blue color is typically caused by iron (Fe2+) in its crystal structure.

Crystal System

• Hexagonal (trigonal) crystal structure.

• Commonly found as elongated, striated prismatic crystals.

Clarity & Luster

• Transparent to translucent.

• Exhibits vitreous (glassy) luster when polished.

Optical Properties

• Strong pleochroism: may show different colors (blue, green, gray) when viewed from different angles.

• Refractive index typically between 1.61 and 1.66.

Hardness

• Mohs hardness: 7–7.5, making it durable for jewelry.

Sources

• Found in Brazil, Afghanistan, Mozambique, Namibia, Nigeria, and Madagascar.

Metaphysical & Collectors’ Appeal (non-scientific)

• Associated with calmness, communication, and emotional clarity.

• Popular with gem collectors due to its rarity and vibrant hue.