Tags: Chemical Substance, Mineral.
Pararealgar is an arsenic sulfide mineral with the chemical formula As4S4 also represented as AsS. It forms gradually from realgar under exposure to light. Its name derives from the fact that its elemental composition is identical to realgar As4S4. It is soft with a Mohs hardness of 1 – 1.5 is yellow orange in colour and its monoclinic prismatic crystals are very brittle easily crumbling to powder.It is one of the sulfides of arsenic and is one of two isomers of As4S4.
