Constituent
Name
Larderellite
IMA name
Larderellite
Class
non-silicate mineral
Compound type
borate
Comments
also written as (NH4)B5O7(OH)2•H2O (MinDat)
Constituent abundance in material
Relevance
main - major
Arrangement
single phase
Mass
0.267 $\pm$ 0.002 $g$
Mass fraction
1.0
Chemical composition
Formula
$(NH_4)B_5O_6(OH)_4$
Chemical formula
(NH4)B5O6(OH)4
Elemental formula
(N+) H8 B5 O6 (O-)4
Isotope mixture type
terrestrial abundance
  Formula Name Family Number min-max Isotope mole fraction State Relevance
$NH_4^+$ Ammonium ion molecule 1 molecular ion main
$B$ Boron element 5 constituent element main
$O$ Oxygen element 6 constituent element main
$(OH)^-$ Hydroxide anion chemical function 4 anionic radical main
Chemical functions
  Function Number
$(OH)^-$ 4
Chemical bonds
  Bond Number Relevance
$\geq N^+-H$ 4 main
$O^--H$ 1
Oxides
Formula $B_{2}O_{3}$ $H_{2}O$
Mass fraction (%) 73.71 15.26
Oxides comments
N2O5 calculated as (NH4)2O = 11.03%

Strunz

Class
borates (06)
Division
pentaborates (06.E)
Family
Ino-pentaborates (06.EB)
Code
06.EB.05

Dana

Major class
carbonates, nitrates, borates (V)
Class
hydrated borates containing hydroxyl or halogen (26)
Type
26.05
Group
-Larderellite- group (26.05.04)
Code
26.05.04.01
Phase type
crystalline
Crystal system
monoclinic
Crystal class
prismatic
Crystal class symbol
2/m (C2h)
Crystal spacegroup
P2(1)/c
Texture
monocrystalline
Molar mass
236.11 $g/mol$
Density
1.905 $g/cm^3$
Refringence type
biaxial
Refringence sign
positive
Birefringence
0.0520
Refraction index $n_{\alpha}$
1.509
Refraction index $n_{\beta}$
1.52
Refraction index $n_{\gamma}$
1.561
Dispersion V
none
Color
yellowish, white
Diaphaneity
translucent