General Information:
Chemical Formula:
CaHAsO4·2(H2O)
Composition:
(Molecular Weight = 216.04 gm)
Calcium 18.55 % Ca
Arsenic 34.68 % As
Hydrogen 2.33 % H
Oxygen 44.44 % O
Empirical Formula:
CaH(AsO4)·2(H2O)
Name Origin:
From the Greek, farmakon, "poison" and lithos, "stone."
Physical Properties:
Cleavage:
[010] Perfect
Color:
white, yellow, reddish white, or grayish white.
Density:
2.6 - 2.73, Average = 2.66
Diaphaniety:
Translucent to opaque
Habits:
Botryoidal - "Grape-like" rounded forms (e.g.. malachite)., Fibrous - Crystals made up of fibers., Encrustations - Forms crust-like aggregates on matrix.
Hardness:
2-2.5 - Gypsum-Finger Nail
Luminescence:
None.
Luster:
Vitreous - Pearly
Streak:
white
More details...