Constituent
Name
Blodite
IMA name
Blodite
Class
non-silicate mineral
Compound type
sulfate
Constituent abundance in material
Relevance
main - minor
Arrangement
in multi-phases
Mass fraction
0.04 $\pm$ 0.1
Chemical composition
Formula
$Na_2Mg(SO_4)_2 \bullet 4(H_2O)$
Chemical formula
Na2Mg(SO4)2•4(H2O)
Elemental formula
(Na+)2 Mg S2 O8 (O-)4 H8
Isotope mixture type
terrestrial abundance
  Formula Name Family Number min-max Isotope mole fraction State Relevance
$Na^+$ Sodium cation element 2 constituent cation main
$Mg$ Magnesium element 1 constituent element main
$(SO_4)^{2-}$ Sulfate anion chemical function 2 anionic radical main
$H_2O$ Water molecule 4 hydration main
Chemical functions
  Function Number Relevance
$(SO_4)^{2-}$ 2
$R-OH$ 2 main
Chemical bonds
  Bond Number Relevance
$-O-H$ 2 main
$\dddot - \dddot - \dddot - S \dddot - O^{-1/2}$ 4
Oxides
Formula $Na_{2}O$ $MgO$ $H_{2}O$ $SO_{3}$
Mass fraction (%) 18.53 12.05 21.54 47.87

Strunz

Class
sulfates - chromates - molybdates - tungstates (07)
Division
sulfates (selenates, etc.) without additional anions, with H2O (07.C)
Family
with medium-sized and large cations (07.CC)
Code
07.CC.50

Dana

Major class
sulfates, chromates, selenates (VI)
Class
hydrated acid and sulfates (29)
Type
where (A+)2B(XO4)2.x(H2O) (29.03)
Group
Blodite group (29.03.03)
Code
29.03.03.01
Phase type
crystalline
Crystal system
monoclinic
Crystal class
prismatic
Crystal class symbol
2/m (C2h)
Crystal spacegroup
P2(1)/c
Molar mass
334.47 $g/mol$
Density
2.23 $g/cm^3$
Refringence type
biaxial
Refringence sign
negative
Birefringence
0.004
Refraction index $n_{\alpha}$
1.483
Refraction index $n_{\beta}$
1.486
Refraction index $n_{\gamma}$
1.487
Dispersion V
relatively strong
Color
colorless, green, yellow, red
Diaphaneity
transparent to translucent