Constituent
- Name
- Alunogen
- IMA name
- Alunogen
- Class
- non-silicate mineral
- Compound type
- sulfate
- Relevance
- main - major
- Arrangement
- in multi-phases
- Mass fraction
- 0.85 $\pm$ 0.1
- Formula
- $Al_2(SO_4)_3 \bullet 17(H_2O)$
- Chemical formula
- Al2(SO4)3•17(H2O)
- Elemental formula
- Al2 S3 O23 (O-)6 H34
- Isotope mixture type
- terrestrial abundance
- Oxides
-
Formula $Al_{2}O_{3}$ $H_{2}O$ $SO_{3}$ Mass fraction (%) 15.72 47.23 37.04
Strunz
- Class
- sulfates - chromates - molybdates - tungstates (07)
- Division
- sulfates (selenates, etc.) without additional anions, with H2O (07.C)
- Family
- with only medium-sized cations (07.CB)
- Code
- 07.CB.45
Dana
- Major class
- sulfates, chromates, selenates (VI)
- Class
- hydrated acid and sulfates (29)
- Type
- where (A)2(XO4)3.x(H2O) (29.08)
- Group
- -Alunogen- group (29.08.06)
- Code
- 29.08.06.01
- Phase type
- crystalline
- Crystal system
- triclinic
- Crystal class
- pinacoidal
- Crystal class symbol
- -1 (Ci)
- Crystal spacegroup
- P-1
- Molar mass
- 648.41 $g/mol$
- Density
- 1.65 - 1.78 $g/cm^3$
- Refringence type
- biaxial
- Refringence sign
- positive
- Birefringence
- 0.0070
- Refraction index $n_{\alpha}$
- 1.473
- Refraction index $n_{\beta}$
- 1.474
- Refraction index $n_{\gamma}$
- 1.48
- Dispersion V
- none
- Color
- white, yellowish white, reddish white, yellowish white
- Diaphaneity
- transparent
- Luster
- vitreous