1st experiment       0.2626
2d "                 0.2634
Mean                 0.2630 grms.

The presence of gold in the residual cyanide solution could not be qualitatively detected.  The potassium cyanide of the solutions obtained by this process should be converted into ferrocyanide by heating with ferrous sulphate and milk of lime, since this substance is not poisonous and can therefore be got rid of without danger.  It would, however, be more economical and, considering the large amount of cyanide present, more profitable to work it up into Prussian blue.

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