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General Information: Chemical Formula:(Na,Li)Al(PO4)(OH,F) Composition:(Molecular Weight = 158.44 gm)Sodium 10.88 % NaLithium 1.10 % LiAluminum 17.03 % AlPhosphorus 19.55 % P Hydrogen 0.48 % H Oxygen 47.97 % O Fluorine 3.00 % F  Empirical Formula: Na0.75Li0.25Al(PO4)OH0.75F0.25Physical Properties: Cleavage:[???] Distinct, [???] Distinct, [???] Distinct Color:white or grayish white. Density:3.04 Diaphaniety:Translucent to opaque Habits:Massive - Uniformly indistinguishable crystals forming large masses., , Hardness:5.5 - Knife Blade Luminescence:Non-fluorescent. Luster:Vitreous - Greasy Streak:whiteMore details...