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
	$\geq N^+-H$	4
	$O^--H$	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

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

Pure color

colorless

Color

yellowish, white

Diaphaneity

translucent

Links

• MinDAT: Larderellite
• WebMineral: Larderellite
• Wikipedia: Larderellite