Howlite
White borate with grey veins, the stone most often dyed to pass as turquoise.
- Family
- Howlite
- Formula
- Ca₂B₅SiO₉(OH)₅
- Mohs
- 3.5
- System
- Monoclinic
Drag to turn
Science
Howlite forms in evaporite borate deposits as chalky white nodules threaded with grey. It is porous and takes dye readily, which is why blue 'turquoise howlite' and every other colour of tumbled stone in a gift shop is usually howlite.
- Mineral
- Howlite
- Formula
- Ca₂B₅SiO₉(OH)₅
- Crystal system
- Monoclinic
- Mohs hardness
- 3.5
- Specific gravity
- 2.58
- Refractive index
- 1.580 to 1.600
- Lustre
- Sub-vitreous
- Colours
- White, Grey veined
Composition
Ca₂B₅SiO₉(OH)₅. Made of Calcium, Boron, Silicon, Oxygen, Hydrogen.
Origin
- CanadaNova Scotia, type locality
- United StatesTick Canyon, California
- Mexico
- Turkey
Filled dots are primary sources
Rarity
Cheap and plentiful; more of it is sold dyed than in its own colour.
- 1 Abundant
- 2 Common
- 3 Uncommon
- 4 Rare
- 5 Exceptional
Hardness
Howlite sits at 3.5 on the Mohs scale. A steel knife will scratch it; it suits pendants and display more than rings.
Energy
Associations from crystal-healing tradition, recorded here as folklore. They are not medical claims.
Chakras
- Crown
- Third Eye
Element
- Air
Zodiac
- Gemini
- Virgo
Planets
- Moon
Properties
- Calm
- Patience
- Sleep
- Quieting the mind
Lore
Named for Henry How, the Nova Scotia chemist who described it in 1868 after quarrymen complained it was spoiling their gypsum. It has no ancient history.
Its modern practice reputation is stillness: the stone for insomnia and short tempers.
- Dye testDyed howlite shows colour concentrated in the veins and scratches white.
- BoronOne of the few common boron minerals besides borax.