Kyanite

Kyanite is an aluminosilicate mineral with the chemical formula Al₂SiO₅. It typically forms in high-pressure, low-temperature metamorphic rocks, such as schists and gneisses, as a result of regional metamorphism. The blue color is due to trace amounts of iron and titanium.

The name “Kyanite” (or Cyanite) is derived from the Greek word “κύανος,” meaning “deep blue.” Alternative names include “Disthene,” meaning “two strengths,” reflecting its distinct hardness in different directions.

Kyanite was a traveler’s stone, providing protection and safe passage during journeys. In ancient times, it aided in navigation and connection with the spiritual realm. In Chinese culture, it is a stone of balance and tranquility.

Heat Resistance: An uncommon property of cyanite is that it can expand up to twice its volume when heated. This predictable expansion allows it to be used in ceramics to maintain desired volumes during firing.
Electrical Insulation: Kyanite is also serviceable as an electrical insulator.

Historically, kyanite was mined in Europe and the Americas for its industrial uses in ceramics and refractory materials. Today, significant deposits are found in Brazil, the United States, and Nepal. Kyanite is mined from metamorphic rock formations, then cut and polished into beads, cabochons, and other jewelry items.

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