| Several supposedly subsulphides of iron have been described from time to time, namely Fe2S, and Fe4S3. The last named is produced when iron is heated in an atmosphere of carbon disulphide vapour, at 1300° to 1400° C., and allowed to cool in the di-sulphide vapour. It is a crystalline body of density 6.96, and soluble in dilute mineral acids evolving hydrogen sulphide and hydrogen. It does not alter when exposed to air, and is oxidised only with difficulty. |