Heptasartorite

Heptasartorite is a very rare mineral^[3] with formula Tl₇Pb₂₂As₅₅S₁₀₈. It belongs to sartorite homologous series.^[2] It is related to other recently approved minerals of the series: enneasartorite and hendekasartorite.^[4][5] All three minerals come from a quarry in Lengenbach, Switzerland, which is famous of thallium minerals.^[6] Chemically similar minerals include edenharterite and hutchinsonite.^[7][8]

Heptasartorite
General
Category	Sulfosalt
Formula	Tl7Pb22As55S108
IMA symbol	Hsat[1]
Crystal system	Monoclinic
Crystal class	Prismatic (2/m) (same H-M symbol)
Space group	P21/c
Unit cell	a = 37.62, b = 7.88, c = 20.07 [Å], β = 101.93° (approximated)
Identification
References	[2][3]