Constituent
Name
Jarosite
IMA name
Jarosite
Class
non-silicate mineral
Compound type
sulfate
Constituent abundance in material
Relevance
main - major
Arrangement
in multi-phases
Chemical composition
Formula
$KFe^{3+}_3(SO_4)_2(OH)_6$
Chemical formula
K(Fe3+)3(SO4)2(OH)6
Elemental formula
(K+) (Fe3+)3 S2 O4 (O-)10 H6
Isotope mixture type
terrestrial abundance
  Formula Name Family Number min-max Isotope mole fraction State Relevance
$K^+$ Potassium(1+) cation element 1 constituent cation main
$Fe^{3+}$ Iron(III) cation element 3 constituent cation main
$(SO_4)^{2-}$ Sulfate anion chemical function 2 anionic radical main
$(OH)^-$ Hydroxide anion chemical function 6 anionic radical main
Chemical functions
  Function Number
$(SO_4)^{2-}$ 2
$(OH)^-$ 6
Chemical bonds
  Bond Number
$\dddot - \dddot - \dddot - S \dddot - O^{-1/2}$ 4
$O^--H$ 1
Oxides
Formula $K_{2}O$ $Fe_{2}O_{3}$ $H_{2}O$ $SO_{3}$
Mass fraction (%) 9.4 47.83 10.79 31.97

Strunz

Class
sulfates - chromates - molybdates - tungstates (07)
Division
sulfates (selenates, etc.) with additional anions, without H2O (07.B)
Family
with medium-sized and large cations (07.BC)
Code
07.BC.10

Dana

Major class
sulfates, chromates, selenates (VI)
Class
anhydrous sulfates containing hydroxyl or halogen (30)
Type
where (A B)2 XO4 Zq (30.02)
Group
Alunite group (Jarosite Subgroup) (30.02.05)
Code
30.02.05.01
Phase type
crystalline
Crystal system
trigonal
Crystal class
pyramidal
Crystal class symbol
3 (C3)
Crystal spacegroup
R3
Molar mass
500.81 $g/mol$
Density
2.9 - 3.3 $g/cm^3$
Refringence type
uniaxial
Refringence sign
negative
Birefringence
0.102 - 0.105
Refraction index $n_{\alpha}$
1.815 - 1.82
Refraction index $n_{\beta}$
1.713 - 1.715
Color
brown, yellow, yellow brown, light yellow
Diaphaneity
translucent
Luster
vitreous