Constituent
Name
Portlandite
Class
non-silicate mineral
Compound type
oxide-hydroxide
Arrangement
homogeneous in multi-phases
Abundance comments
Unknown mass fraction of Portlandite. Each mole of Portlandite transformed produce one mole of carbonate: Calcite + Aragonite
Formula
$Ca(OH)_2$
Chemical formula
Ca(OH)2
Elemental formula
O2 H2 Ca
Isotope mixture type
terrestrial abundance
  Formula Name Family Number min-max Isotope mole fraction State Relevance
$Ca$ Calcium element 1.0 constituent element main
$O$ Oxygen element 2.0 constituent element main
$H$ Hydrogen element 2.0 constituent element main
Chemical functions
  Function Number
$\bullet (OH)^-$ 2
Chemical bonds
  Bond Number
$H-O^-$ 1
Oxides
Formula H2O CaO
Mass fraction (%) 24.31 975.6

Strunz

Class
oxides - hydroxides - arsenites (04)
Division
hydroxides (without V or U) (04.F)
Family
Hydroxides with OH, without H2O; sheets of edge-sharing octahedral (04.FE)
Code
04.FE.05

Dana

Major class
oxides and hydroxides (III)
Class
hydroxides and oxides containing hydroxyl (06)
Type
where X++ (OH)2 (06.02)
Group
Brucite group (Rhombohedral: P-3m1) (06.02.01)
Code
06.02.01.04
Phase type
crystalline
Crystal system
trigonal
Crystal class
hexagonal-scalenohedral
Crystal class symbol
-3m (D3d)
Crystal spacegroup
P-3m1
Crystal sites
Label Nb Wp Atom Atom coordinence Atom occupancy Atom oxidation state
H 6 6i.m.  $H$ linear I 0.333
Ca 1 1a-3m.  $Ca^{2+}$ trigonal prismatic VI 1.0
O 2 6i.m.  $O$ 1.0
Molar mass
74.09 $g/mol$
Density
2.23 $g/cm^3$
Refringence type
uniaxial
Refringence sign
negatif
Birefringence
0.0270
Refraction index $n_{\alpha}$
1.547
Refraction index $n_{\beta}$
1.574
Color
light yellow
Diaphaneity
transparent
Luster
pearly