Fairfieldite

General Information:
 Chemical Formula:
Ca2(Mn,Fe++)(PO4)2·2(H2O)
 Composition:
(Molecular Weight = 361.29 gm)
Calcium 22.19 % Ca
Manganese 11.40 % Mn
Iron 3.86 % Fe
Phosphorus 17.15 % P 
Hydrogen 1.12 % H 
Oxygen 44.28 % O 
 Empirical Formula:
Ca2Mn2+0.75Fe2+0.25(PO4)2·2(H2O)
Physical Properties:
 Cleavage:
[???] Perfect, [???] Distinct
 Color:
greenish white, white, or light yellow.
 Density:
3.1
 Diaphaniety:
Transparent
 Habits:
Foliated - Two dimensional platy forms., Fibrous - Crystals made up of fibers., Euhedral Crystals - Occurs as well-formed crystals showing good external form.
 Hardness:
3.5 - Copper Penny
 Luminescence:
Non-fluorescent.
 Luster:
Vitreous - Pearly
 Streak:
white
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