Constituent Orpiment | SSHADE

Constituent

Name: Orpiment
IMA name: Orpiment

Class: non-silicate mineral
Compound type: sulfide
Comments: Common impurities: Hg, Ge, Sb

Constituent abundance in material

Relevance: main - major
Arrangement: in multi-phases

Chemical composition

Formula: $As_2S_3$
Chemical formula: As2S3
Elemental formula: As2 S3
Isotope mixture type: terrestrial abundance

	Formula	Name	Family	Number min-max	Isotope mole fraction	State	Relevance
	$As$	Arsenic	element	2		constituent element	main
	$S$	Sulfur	element	3		constituent element	main

Composition comments: Polymeric solid

Chemical functions and bonds

Chemical bonds

	Bond	Number
	$As-S$	6

Oxides composition

Oxides comments: As: 60.9%, S: 39.1%

Classifications

Strunz

Class: sulfides - sufosalts (02)
Division: sulfides of arsenic, alkalies; sulfides with halide, oxide, hydroxide, H2O (02.F)
Family: With As, (Sb), S (02.FA)
Code: 02.FA.30

Dana

Major class: sulfides (II)
Class: sulfides - including selenides and tellurides (02)
Type: where Am Bn Xp, with (m+n):p=2:3 (02.11)
Group: Orpiment group (02.11.01)
Code: 02.11.01.01

Phase type: crystalline

Crystallography

Crystal system: monoclinic
Crystal class: prismatic
Crystal class symbol: 2/m (C2h)
Crystal spacegroup: P2(1)/m

Physical properties

Molar mass: 246.04 $g/mol$
Density: 3.49 - 3.56 $g/cm^3$

Optical properties

Refringence type: biaxial
Refringence sign: negative
Birefringence: 0.620
Refraction index $n_{\alpha}$: 2.40
Refraction index $n_{\beta}$: 2.81
Refraction index $n_{\gamma}$: 3.02
Dispersion V: r > v strong
Color: lemon yellow, brownish yellow, orange yellow
Diaphaneity: transparent to translucent
Luster: pearly