Constituent
- Name
- Vermiculite
- IMA name
- Vermiculite
- Class
- silicate mineral
- Compound type
- phyllosilicate
- Relevance
- main - major
- Arrangement
- single phase
- Mass fraction
- 1.0
- Formula
- $(Mg,Fe^{2+},Al)_3(Al,Si)_4O_{10}(OH)_2\bullet 4(H_2O)$
- Chemical formula
- (Mg,Fe2+,Al)3(Al,Si)4O10(OH)2•4(H2O)
- Elemental formula
- (Al)0-7 (Mg)0-3 (Fe2+)0-3 (Si)0-4 O16 H10
- Isotope mixture type
- terrestrial abundance
- Composition comments
- Strong variation of Si and Al proportion. Common impurities: Na, K, Ca
- Oxides
-
Formula $Al_{2}O_{3}$ $FeO$ $MgO$ $SiO_{2}$ $H_{2}O$ Mass fraction (%)
Strunz
- Class
- silicates (09)
- Division
- phyllosilicate (09.E)
- Family
- Phyllosilicates with mica sheets, composed of tetrahedral and octahedral nets (09.EC)
- Code
- 09.EC.50
Dana
- Major class
- silicates (VIII)
- Class
- phyllosilicate sheets of six-membered rings (71)
- Type
- with 2:1 layers (71.02)
- Group
- Mica group (Hydromica subgroup) (71.02.02d)
- Code
- 71.02.02d.03
- Phase type
- crystalline
- Crystal system
- monoclinic
- Crystal class
- prismatic
- Crystal class symbol
- 2/m (C2h)
- Crystal spacegroup
- C2/m
- Texture
- monocrystalline
- Molar mass
- 504.19 $g/mol$
- Density
- 2.3-2.7 $g/cm^3$
- Refringence type
- biaxial
- Refringence sign
- negative
- Birefringence
- 0.0200
- Refraction index $n_{\alpha}$
- 1.525-1.561
- Refraction index $n_{\beta}$
- 1.545-1.581
- Refraction index $n_{\gamma}$
- 1.545-1.581
- Dispersion V
- weak, r > v
- Color
- Colorless, Green, Gray white, Yellow brown, Brown, Yellow
- Diaphaneity
- translucent
- Luster
- vitreous