The liquid is now run into neutralizing tanks containing sodium carbonate, and, after settling, the supernatant liquid, termed "light liquor," is run through bag filters and then on to bone-char filters, which have been previously used for the "heavy liquor."
The supernatant liquid is led into settling tanks, where a further amount of "gold is deposited, r and is then filtered through sawdust or sand, the sawdust being afterwards burnt and the gold separated from the ashes and the sand treated in the chloridizing vat.
The slime is cleaned out fortnightly or monthly, the zinc turnings being cleaned by rubbing and the supernatant liquor allowed to settle in the precipitating boxes or in separate vessels.
Discard the excess supernatant and resuspend the pellet in the 100 μl from the pipette.
The supernatant was applied to the first column using a 5 ml pipette and allowed to pass over the resin.