Tourmaline
Real mineral · uncommon · XY₃Z₆(T₆O₁₈)(BO₃)₃V₃W
A complex boron silicate with one of the widest compositional ranges of any mineral. Generates an electrical charge when compressed or heated due to its piezoelectric and pyroelectric properties. Bi-coloured crystals are common.
Identity
- Formula
- XY₃Z₆(T₆O₁₈)(BO₃)₃V₃W
- Chemical class
- silicate
- Mineral group
- Paraíba Tourmaline
- Also known as
- Schorl (black), Rubellite (red-pink), Indicolite (blue), Verdelite (green), Paraiba (neon blue-green)
Crystallography
- Crystal system
- trigonal
- Habits
- prismatic, columnar
- Fracture
- conchoidal
Physical properties
- Mohs hardness
- 7.5
- Density
- 3.1 g/cm³
- Luster
- vitreous
- Colors
- black, brown, green, blue, red, pink, yellow, colorless, multicolored
- Streak
- white
- Transparency
- transparent, translucent, opaque
Geology
- Origins
- igneous, metamorphic, hydrothermal
- Host rocks
- granite, pegmatite, schist
- Associated minerals
- Quartz, feldspar, Mica, Beryl
- Geography
- Brazil, Afghanistan, Pakistan, Madagascar, USA
Classification
- Rarity
- uncommon
- Gem quality
- Yes
Arcane properties
- Affinity
- arcane, storm
- Effects
- warding, elemental lightning
- Planar origin
- Material Plane
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