Mineral phase
IMA name
Caryopilite
Class
silicate mineral
Compound type
phyllosilicate
Comments
Molar mass range for x=0.5-1 - Crystal structure not well know: possibly monoclinic-domatic (m), space group Cm
Formula
$(Mn^{2+}_x,Mg_{1-x})_3.Si_2O_5(OH)_4 \ \ \ \ \ $ where $x=0.5-1$
Chemical formula
(Mn2+,Mg)3Si2O5(OH)4
Elemental formula
(Mg)0-1.5 (Mn2+)1.5-3 Si2 O9 H4
Isotope mixture type
terrestrial abundance
  Formula Name Family Number min-max Isotope mole fraction State Relevance
$Mg$ Magnesium element 0 - 1.5 constituent element main
$Mn^{2+}$ Manganese(II) cation element 1.5 - 3 constituent element main
$Si$ Silicon element 2 constituent element main
$O$ Oxygen element 9 constituent element main
$H$ Hydrogen element 4 constituent element main
Composition comments
Common substitution: Zn, Fe^{2+} substituting Mn^{2+} and Mg, As substituting Si, Cl substituting OH (sometimes in the formula: $(Mn^{2+},Mg,Zn,Fe^{2+})_3(Si,As)_2O_5(OH,Cl)_4$) - Common impurities: Al, Ca, F
Chemical functions
  Function Number
$(OH)^-$ 4
Chemical bonds
  Bond Number
$O^--H$ 1
Oxides
Formula $MnO$ $MgO$ $SiO_{2}$ $H_{2}O$
Mass fraction (%)

Strunz

Class
silicates (09)
Division
phyllosilicate (09.E)
Family
with kaolinite layers composed of tetrahedral and octahedral nets (09.ED)
Code
09.ED.15

Dana

Major class
silicates (VIII)
Class
phyllosilicate sheets of six-membered rings (71)
Type
with 1:1 layers (71.01)
Group
Serpentine group (Lizardite subgroup) (71.01.02b)
Code
71.01.02b.01
Phase type
crystalline
Crystal system
monoclinic
Crystal class
prismatic
Crystal class symbol
2/m (C2h)
Crystal spacegroup
C2/m
Molar mass
323.2 - 369.16 $g/mol$
Density
2.87 $g/cm^3$
State NTP
solid
Refringence type
biaxial
Refringence sign
negative
Birefringence
0.026 - 0.030
Refraction index $n_{\alpha}$
1.606 - 1.62
Refraction index $n_{\beta}$
1.632 - 1.65
Refraction index $n_{\gamma}$
1.632 - 1.65
Dispersion V
weak
Pure color
yellow
Color
yellow, reddish brown, greenish brown, orange brown
Diaphaneity
transparent to translucent
Luster
vitreous