Natron

Natron is a naturally occurring mixture of hydrated sodium carbonate (soda ash, Na2CO3·10 H2O) and about 17% sodium bicarbonate (baking soda, NaHCO3) along with small quantities of household salt (sodium chloride) and sodium sulfate. Natron is white to colorless when pure, varying to gray or yellow with impurities. Natron deposits occur naturally as a part of saline lake beds in arid environments. Historically natron had many practical applications which still resonate in the wide modern use of its constituent mineral components.
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n. bicarbonate of soda, baking soda, sodium bicarbonate

n. natron

(n.)
Native sodium carbonate.
  

General Information:
 Chemical Formula:
Na2CO3·10(H2O)
 Composition:
(Molecular Weight = 286.14 gm)
Sodium 16.07 % Na
Hydrogen 7.05 % H 
Carbon 4.20 % C 
Oxygen 72.69 % O 
 Empirical Formula:
Na2(CO3)·10(H2O)
 Environment:
Saline lake beds in arid environments.
 IMA Status:
Approved IMA 1960
 Locality:
Ragtown, Nevada, USA.
 Name Origin:
From the Latin for "soda."
Physical Properties:
 Cleavage:
[001] Distinct, [010] Imperfect
 Color:
white, gray, colorless, or yellow.
 Density:
1.42 - 1.47, Average = 1.44
 Diaphaniety:
Transparent to Translucent
 Habits:
Encrustations - Forms crust-like aggregates on matrix., Efflorescences - Crystals covering matrix, generally produced from transpiro-evaporation.,
 Hardness:
1 - Talc
 Luminescence:
Phosphorescent.
 Luster:
Vitreous (Glassy)
 Streak:
white
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