Cupric arsenides

Arsine reacts with cupric chloride solution to give cupric arsenide. Oxidation with stannic chloride, SnCR, forms hydrogen diarsenide, AS4H2. It reacts with dilute silver nitrate solution forming metallic silver. 

Tri-copper Di-arsenide, Cu3As2, is formed when arsine acts on a solution of copper sulphate,17 or on dry copper sulphate or chloride 18 by subjecting a suitable mixture of the powdered elements to a pressure of 6500 atm. 19 by reducing cupric arsenite with fused potassium... 

Salter (1869) describes producing a calcined form with an olive colour, stating that cupric arsenite, when heated, gives off arsenious acid and water, leaving a residue of arsenide of copper and copper arseniate. ... 

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