Hemimorphite
Mineral Zn4Si2O7(OH)2·H2O
Also called Calamine
About it
Thin blades in fan-shaped sprays, or sky-blue botryoidal crusts from Yunnan, China, formed where zinc ores weather; Mapimí, Mexico, gives clear blades. Its crystals end differently at each end.
- Type
- Mineral
- Group
- Silicate (sorosilicate), hemimorphite group
- Formula
- Zn4Si2O7(OH)2·H2O
- Hardness (Mohs)
- 4.5–5
- Specific gravity
- 3.4–3.5
- Streak
- white
- Lustre
- vitreous (glassy), silky
- Crystal system
- Orthorhombic
- Colours
- colourless, white, sky blue, blue-green, pale brown
- Transparency
- transparent, translucent
- Cleavage and fracture
- perfect in one direction
Typical values: real specimens vary. For more, see mindat.org.