Amblygonite
Mineral LiAl(PO4)F
About it
A lithium phosphate of granite pegmatites, white to pale yellow, with cleavage that recalls feldspar. Much material sold under this name is really montebrasite; clear yellow gem crystals come from Brazil.
- Type
- Mineral
- Group
- Phosphate, amblygonite group
- Formula
- LiAl(PO4)F
- Hardness (Mohs)
- 5.5–6
- Specific gravity
- 3–3.1
- Streak
- white
- Lustre
- vitreous (glassy), pearly, greasy
- Crystal system
- Triclinic
- Colours
- white, cream, pale yellow, pale green, lilac, colourless
- Transparency
- transparent, translucent
- Cleavage and fracture
- perfect in one direction, good in another; uneven fracture
Typical values: real specimens vary. For more, see mindat.org.