Blue kyanite is an aluminum silicate mineral renowned for its distinctive blade-like crystal formations and vibrant blue coloration that ranges from pale sky blue to deep sapphire. This unique gemstone exhibits perfect cleavage along its length, creating naturally flat, striated crystals that often appear translucent with a pearly to vitreous luster. Blue kyanite is particularly notable for its unusual property of having different hardness levels depending on the direction of measurement—softer along the length of the crystal and harder across its width—making it a fascinating specimen for both collectors and metaphysical practitioners.
Specifications:
- Color range: Pale sky blue to deep sapphire blue with natural color zoning and striations along crystal faces
- Hardness: 4 to 5 Mohs scale along the length, 6 to 7 Mohs scale across the width (directional hardness)
- Origin: Primarily Brazil, Nepal, Kenya, Myanmar, Switzerland, and North Carolina USA
- Sizes: Natural blades range from small 1-inch specimens to large 6+ inch crystals; cut stones typically 8mm to 25mm
- Shapes: Natural blade formations, tumbled stones, rough specimens, and occasional cabochons (challenging to cut due to cleavage)
- Transparency: Transparent to translucent with excellent clarity in high-quality specimens
- Luster: Vitreous to pearly with natural striations creating light play along crystal faces
- Crystal habit: Distinctive flat, blade-like crystals with perfect cleavage and natural terminations
