Mineral phase
IMA name
Thermonatrite
CAS number
5968-11-6
Class
non-silicate mineral
Compound type
carbonate
Formula
$Na_2CO_3 \bullet (H_2O)$
Chemical formula
Na2CO3•(H2O)
Elemental formula
Na2 C O4 H2
Isotope mixture type
terrestrial abundance
  Formula Name Family Number min-max Isotope mole fraction State Relevance
$Na$ Sodium element 2 constituent element main
$C$ Carbon element 1 constituent element main
$O$ Oxygen element 4 constituent element main
$H$ Hydrogen element 2 constituent element main
Chemical functions
  Function Number
$(CO_3)^{2-}$ 1
Chemical bonds
  Bond Number
$\dddot - \dddot - C \dddot - O^{-2/3}$ 3
Oxides
Formula $Na_{2}O$ $CO_{2}$ $H_{2}O$
Mass fraction (%) 49.98 35.49 14.53

Strunz

Class
carbonates - nitrates (05)
Division
carbonates without additional anions, with H2O (05.C)
Family
with large cations (alkali and alkali-earth carbonates) (05.CB)
Code
05.CB.05

Dana

Major class
carbonates, nitrates, borates (V)
Class
hydrated carbonates (15)
Type
where A+(XO3)·x(H2O) (15.01)
Group
-Thermonatrite- group (15.01.01)
Code
15.01.01.01
Phase type
crystalline
Crystal system
orthorhombic
Crystal class
dipyramidal
Crystal class symbol
mmm (D2h)
Crystal spacegroup
Pmmm
Comments
also class pyramidal mm2 (C2v), space group Pca21
Molar mass
124.00 $g/mol$
Density
2.255 $g/cm^3$
State NTP
solid
Refringence type
biaxial
Refringence sign
negative
Birefringence
0.104
Refraction index $n_{\alpha}$
1.420
Refraction index $n_{\beta}$
1.506
Refraction index $n_{\gamma}$
1.524
Dispersion V
relatively strong
Pure color
colorless
Color
colorless, white, gray, yellow
Diaphaneity
transparent
Luster
vitreous