Constituent
Name
Goldichite
IMA name
Goldichite
Class
non-silicate mineral
Compound type
sulfate
Constituent abundance in material
Relevance
main - major
Arrangement
in multi-phases
Mass fraction
0.18 $\pm$ 0.1
Chemical composition
Formula
$KFe^{3+}(SO_4)_2 \bullet 4(H_2O)$
Chemical formula
K(Fe3+)(SO4)2•4(H2O)
Elemental formula
(K+) (Fe3+) S2 O8 (O-)4 H8
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 1 constituent cation 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 $K_{2}O$ $Fe_{2}O_{3}$ $H_{2}O$ $SO_{3}$
Mass fraction (%) 13.11 22.23 20.07 44.59

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.40

Dana

Major class
sulfates, chromates, selenates (VI)
Class
hydrated acid and sulfates (29)
Type
where AB(XO4)2.x(H2O) (29.05)
Group
-Goldichite- group (29.05.02)
Code
29.05.02.01
Phase type
crystalline
Crystal system
monoclinic
Crystal class
prismatic
Crystal class symbol
2/m (C2h)
Crystal spacegroup
P2(1)/c
Molar mass
359.13 $g/mol$
Density
2.43 $g/cm^3$
Refringence type
biaxial
Refringence sign
positive
Birefringence
0.0470
Refraction index $n_{\alpha}$
1.582
Refraction index $n_{\beta}$
1.602
Refraction index $n_{\gamma}$
1.629
Color
light yellow green