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Prevent mercury poisoning
Artisinal gold (or silver) miners can prevent mercury poisoning by using a
mercury retort. A mercury retort captures mercury gas before it gets into the
air. This prevents miners and others from breathing the poison, and allows
miners to save money by reusing mercury rather than losing it to the air.
Always separate gold from mercury in the open air or in a well-ventilated
area. This will reduce the amount of mercury fumes that collect on, and in,
the bodies of people nearby. Wear thick gloves when handling mercury.
Some gold miners simply put a banana leaf over the gold heating pan to
capture mercury. When heated, the mercury turns to gas, and turns back to
liquid on the leaf. Covering the heating pan with a leaf is much better than
leaving it uncovered. But this still allows the mercury to poison the worker
and the environment, and the mercury is not recovered. A better solution is to
use a closed retort.
There are many kinds of mercury retorts. All of them require strong,
directed heat. A blowtorch or a fire with an air blower will help to recover all
the gold as quickly as possible.
Howbtconbmxnackbe a bowl-style retort
Large stainless steel bowl with
a hole in the bottom
Enamel bowl to hold amalgam
sits in the hole in the outer bowl
Put a bed of sand in the steel
bowl and around the enamel bowl
Glass bowl upside down over
enamel bowl in the bed of sand
Amalgam is placed in the
enamel bowl before heating
Aim torch at the bottom of the
enamel bowl to heat the amalgam
The heat will turn the mercury
to vapor, which will rise to the
glass bowl, and then turn to
liquid and run down the sides
into the sand. The gold will be
left in the enamel bowl.
Fireproof stand to hold retort
A Community Guide to Environmental Health 2012