Brushite
Mineral CaHPO4·2H2O
About it
Soft, pale crusts and small crystals formed where guano reacts with limestone or phosphate rock, as in caves and on seabird islands. Named for American mineralogist George Brush.
- Type
- Mineral
- Group
- Phosphate
- Formula
- CaHPO4·2H2O
- Hardness (Mohs)
- 2.5
- Specific gravity
- 2.3–2.35
- Streak
- white
- Lustre
- vitreous (glassy), pearly
- Crystal system
- Monoclinic
- Colours
- colourless, white, pale yellow
- Transparency
- transparent, translucent
- Cleavage and fracture
- perfect in one direction
Typical values: real specimens vary. For more, see mindat.org.