Archerite

Archerite is a mineral that occurs as a component of stalactites and crusts on the walls of caves containing bat guano deposits.
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General Information:
 Chemical Formula:
(K,NH4)H2PO4
 Composition:
(Molecular Weight = 130.82 gm)
Potassium 22.42 % K 
Phosphorus 23.68 % P 
Hydrogen 2.31 % H 
Nitrogen 2.68 % N 
Oxygen 48.92 % O 
 Empirical Formula:
K0.75(NH4)0.25H2(PO4)
 IMA Status:
Approved IMA 1975
Physical Properties:
 Cleavage:
None
 Color:
beige or white.
 Hardness:
2 - Gypsum
 Streak:
white
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