mineral
Howlite
Calcium borosilicate hydroxide (Ca2B5SiO9(OH)5)
Hardness: 3.5 (Mohs), Color: White to milky white with grey or brown veining, Luster: Sub-vitreous to dull, Crystal Structure: Monoclinic (usually massive), Specific Gravity: 2.53-2.59
- Hardness
- 3
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Physical properties
Hardness: 3.5 (Mohs), Color: White to milky white with grey or brown veining, Luster: Sub-vitreous to dull, Crystal Structure: Monoclinic (usually massive), Specific Gravity: 2.53-2.59
Formation & geological history
Formed in evaporite deposits within sedimentary basins, typically associated with saline lake environments where boron is present in the groundwater.
Uses & applications
Commonly used in jewelry as beads or cabochons. It is highly porous and frequently dyed blue to imitate Turquoise or red to imitate Coral.
Geological facts
Named after Henry How, a Canadian mineralogist who first described it in Nova Scotia in 1868. In the metaphysical community, it is often called the 'calming stone'.
Field identification & locations
Identified by its distinctive spider-web veining and chalky white appearance. It is much softer than quartz or turquoise, making it easy to scratch with a copper coin or knife. Found primarily in California and Canada.
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Sandstone (with potential mineral staining/concretions)
Arenite (SiO2 based)
sedimentary
Sandstone with Mineral Veining or Crust
Sedimentary Sandstone (mostly SiO2 with Fe2O3 tinting)
sedimentary
Schist
Schist
Metamorphic
Epidote
Epidote | Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH)
metamorphic
Gypsum (variety Selenite or Alabaster)
Calcium sulfate dihydrate (CaSO4·2H2O)
Mineral
Nephrite Jade
Nephrite
Mineral/Rock