Englishite

General Information:
 Chemical Formula:
K3Na2Ca10Al15(PO4)21(OH)7·26(H2O)
 Composition:
(Molecular Weight = 3,550.62 gm)
Potassium 3.30 % K 
Sodium 1.29 % Na
Calcium 11.29 % Ca
Aluminum 11.40 % Al
Phosphorus 18.32 % P 
Hydrogen 1.67 % H 
Oxygen 52.72 % O 
 Empirical Formula:
K3Na2Ca10Al15(PO4)21(OH)7·26(H2O)
 Environment:
In variscite nodules.
 Locality:
Clay Canyon, Fairfield, Utah CounTy, Utah, USA.
 Name Origin:
Named for George L. English (1864-1944), American mineral dealer and collector.
Physical Properties:
 Cleavage:
[001] Perfect
 Color:
colorless or white.
 Density:
2.68
 Diaphaniety:
Transparent to Translucent
 Habits:
Micaceous - Platy texture with "flexible" plates., Aggregates - Made of numerous individual crystals or clusters., Friable - Loosley cohesive material that granulates with your finger s.
 Hardness:
3 - Calcite
 Luminescence:
Non-fluorescent.
 Luster:
Vitreous - Pearly
 Streak:
white
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