Heptasartorite is a very rare mineral with formula Tl7Pb22As55S108. It belongs to sartorite homologous series.Topa, D., Stroeger, B., Makovicky, E., Berlepsch, P., and Stanley, C., 2015. Heptasartorite, IMA 2015-073. CNMNC Newsletter No. 28, December 2015, 1861; Mineralogical Magazine 79, 1859–1864 It is related to other recently approved minerals of the series: enneasartorite and hendekasartorite. All three minerals come from a quarry in Lengenbach, Switzerland, which is famous of thallium minerals. Chemically similar minerals include edenharterite and hutchinsonite.
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