Trithioarsenite
Trithioarsenite, also called sulfarsenite, is the trianion. It is a pyramidal anion, as is typical of other compounds. It is generated by treatment of [Arsenic trisulfide|] with a sulfide:
A fundamental synthetic trithioarsenite is, which features the pyramidal.
Thioarsenites are components of many sulfosalt minerals. An example is relatively common mineral proustite,, which is silver trithioarsenite.