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“Bite-Size Bits of Local, National, and Global History”
“Bite-Size Bits of Local, National, and Global History”
San Jose in Santa Clara County, California — The American West (Pacific Coastal)
 

Hoeing Table and Cleaning Tank

 
 
Hoeing Table and Cleaning Tank Marker image. Click for full size.
By Barry Swackhamer, November 17, 2011
1. Hoeing Table and Cleaning Tank Marker
Inscription. Hoeing tables and cleaning tanks were used to purify mercury as the final step in the process of converting cinnabar to mercury. Mercury collected in the condensers of a furnace or retort was contaminated with soot, water, dust, sublimed sulphur [sic] and other oxide metals, all of which was called “soot” or “mud.” To separate these impurities from the mercury, mud was spread on the hoeing table and mixed with quicklime (calcium oxide – CaO). The lime absorbed the water and captured other impurities, allowing the mercury to flow freely.

The two examples above left are “manual” hoeing tables whereupon a worker used a hoe to thoroughly mix mud with lime and allow mercury globules to coalesce and flow out of a spigot into a catching bucket. The cleaning tank, below left, was powered by an electric motor. The motor turned four rubber paddles to mix the mud with water and lime and allow clean mercury to settle to the bottom of the tank, where it was drawn off through a spigot. This type of cleaning tank was able to operate nearly continuously, freeing the worker to perform other duties.

These three tables were used in the Guadalupe mine from the 1940s until the mine closed in the 1970s. The Guadalupe Rubbish Company donated the tables to NAQCPA in 1987.
 
Erected
Hoeing Table and Cleaning Tank Marker image. Click for full size.
By Barry Swackhamer, November 17, 2011
2. Hoeing Table and Cleaning Tank Marker
2011 by New Almaden Quicksilver County Park Association, California State Society - Daughters of the American Revolution and Santa Clara County Parks and Recreation.
 
Location. 37° 10.405′ N, 121° 49.573′ W. Marker is in San Jose, California, in Santa Clara County. Marker can be reached from Almaden Road. Click for map. The Hacienda Mining Display is a short walk on the Deep Gulch Trail from the Almaden Quicksilver County Park parking lot. Marker is at or near this postal address: 21731 Almaden Road, San Jose CA 95120, United States of America.
 
Other nearby markers. At least 8 other markers are within walking distance of this marker. Cornish Pump (here, next to this marker); Mercury Storage Vault (here, next to this marker); Shaker-Concentrator (here, next to this marker); Hacienda Mining Display (here, next to this marker); D Retort and Condensing System (here, next to this marker); Gould Rotary Furnace and Condensing System (a few steps from this marker); Skip Loader (a few steps from this marker); Mine Air Compressors (a few steps from this marker). Click for a list of all markers in San Jose.
 
Categories. Industry & CommerceNatural Resources
 
Hacienda Mining Display image. Click for full size.
By Barry Swackhamer, November 17, 2011
3. Hacienda Mining Display
 
 
Credits. This page originally submitted on , by Barry Swackhamer of San Jose, California. This page has been viewed 317 times since then and 3 times this year. Photos:   1, 2, 3. submitted on , by Barry Swackhamer of San Jose, California. • Syd Whittle was the editor who published this page. This page was last revised on June 16, 2016.
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