Calcium Hydroxyhydrosulphide, Ca(SH)(OH).3H₂O

Calcium Hydroxyhydrosulphide, Ca(SH)(OH).3H₂O, is obtained by the action of a little water or lime on the hydrosulphide, or on the sulphide, or of the sulphide or sulphuretted hydrogen on calcium hydroxide as in the purification of coal-gas. It is obtained in four-sided prisms or fine needles which lose hydrogen sulphide in the air, becoming yellow and opaque. It readily dissolves in water, forming the hydrate, and it absorbs carbon bisulphide with the production of a basic thio- carbonate, 2Ca(OH)₂.CaCS₃.10H₂O.