Wow Photo Wednesday

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This photo does have a lot of neat and fascinating wow! From my research of turn of the century mining methods and pouring through period mining and milling books. Here is what I believe that the picture depicts. This is a small operation miner using a portable mercury amalgam retort. He has a iron tripod holding the retort above a hot coal fire. The retort is made of iron, opens like a plastic easter egg and closes air tight. The pipe that goes up out of top the retort is for the vaporized mercury to escape and pass through the condensing water jacket. Once cooled back into a liquid, the mercury will run down into the lower container to be collected and reused over again. This also separates the precious metal from the mercury. The water jacket is the thicker tube in the middle where water in the other tube from the wooden barrel flows through by gravity.

The amalgam can be from many different concentrating sources, a sluice box, stamp mill pans, ball and rod mills, clean up barrel, etc. Mercury attracts fine gold and other precious metals. For example for a stamp mill, mercury is spread on a copper plate the same width of the output of the stamp battery box outflow. The stamp mill pulp flows over the plate and down the sluice. Once the mercury is very concentrated (amalgam) it is removed from the copper plate with a putty knife or scraper. This typically put into a durable container and into a locked safe in the mill. Once a good amount of amalgam is collected, it would be processed in a retort. Once the mercury is vaporized off the concentrate, mostly precious metal is left in the bottom of the retort. These wanted materials are then sent to a smelter to be purified into bullion and poured into a bar or button.

The gasses that come out of the lower condensed end can contain traces of mercury vapor, and other noxious gasses from other minerals in the concentrate. This is why they are doing this task outside. Hopefully the man tending the retort is sitting upwind. Hopefully too he has also washed his hands well before packing his pipe with tobacco. If this is his steady day to day job at the mill his life expectancy is going to be shorter than normal. Someone always had to tend the retort, as the “pay” is in that iron jar.

Notice also the mercury flasks on the ground by the wood crate. They are cylinders with a small nipple on the top. On the wood blocks under the water barrel is a wide funnel and a narrow funnel. These are likely to pour the condensed mercury back into the flasks. These flasks when full, can weigh around 76 pounds. Mercury is a super heavy element and possibly that is why there is a pulley hoist above the retort and a wheel barrow in the background. Mercury was also sold in glass bottles and crock jugs that look like moonshine jugs. Hence the play on words: miner and his still.

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