Diaspore
Mineral AlO(OH)
Also called Zultanite and Csarite
About it
Platy to bladed crystals with one perfect cleavage, much harder than other aluminium hydroxides. Mines near Milas, Turkey, yield gem crystals that shift from green to pink in different light; it crackles apart when heated.
- Type
- Mineral
- Group
- Hydroxide, diaspore group
- Formula
- AlO(OH)
- Hardness (Mohs)
- 6.5–7
- Specific gravity
- 3.3–3.5
- Streak
- white
- Lustre
- vitreous (glassy), pearly
- Crystal system
- Orthorhombic
- Colours
- colourless, white, yellow, green, pink, brown, colour-change green to pink
- Transparency
- transparent, translucent
- Cleavage and fracture
- perfect in one direction; conchoidal fracture
Typical values: real specimens vary. For more, see mindat.org.