salpeter

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nm. saltpeter, nitre, niter, natural form of potassium nitrate, white crystalline salt used in the manufacture of gunpowder and fertilizer

n. saltpetre, saltpeter, nitre, niter

General Information:
 Chemical Formula:
KNO3
 Composition:
(Molecular Weight = 101.10 gm)
Potassium 38.67 % K 
Nitrogen 13.85 % N 
Oxygen 47.47 % O 
 Empirical Formula:
K(NO3)
 Environment:
Efflorescence on cavern walls.
 Locality:
Limestone caves in Kentucky and Tennessee.
 Name Origin:
Named derived from Herbraic neter, used in ancient times for alkaline salts extracted by water from vegetable ashes.
Physical Properties:
 Cleavage:
[001] Very Good, [010] Good
 Color:
colorless, white, or gray.
 Density:
2.1 - 2.11, Average = 2.1
 Diaphaniety:
Transparent
 Habits:
Encrustations - Forms crust-like aggregates on matrix., Massive - Granular - Common texture observed in granite and other igneous rock.,
 Hardness:
2 - Gypsum
 Luster:
Vitreous (Glassy)
 Streak:
white
More details...

nitre, nitric